[WASSERSTEIN PERELLA & CO. LOGO]




                                                                  CONFIDENTIAL
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                          PRELIMINARY PRESENTATION TO THE SPECIAL COMMITTEE OF
                                 THE BOARD OF DIRECTORS OF MYCOGEN CORPORATION

                                                                 JUNE 25, 1998







                         WASSERSTEIN PERELLA & CO., INC.

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MYCOGEN CORPORATION                                          TABLE OF CONTENTS
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TABLE OF CONTENTS


          1.  BACKGROUND OF THE PROPOSED TRANSACTION

          2.  REVIEW OF MYCOGEN

          3.  REVIEW OF DOW

          4.  PRELIMINARY VALUATION ANALYSIS

              A. REVIEW OF ANALYST PERSPECTIVES

              B. DISCOUNTED CASH FLOW ANALYSIS (DCF)

              C. COMPARABLE COMPANY TRADING ANALYSIS

              D. COMPARABLE ACQUISITION ANALYSIS

          5.  STRATEGIC ALTERNATIVES

          6.  NEXT STEPS

          7.  APPENDIX

              A. WP&CO. JUNE 10TH LETTER TO DOW

              B. DOW'S RESPONSES TO WP&CO.'S JUNE 10TH LETTER


                                                     WASSERSTEIN PERELLA & CO.
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MYCOGEN CORPORATION
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                        -----------------------------
                              BACKGROUND OF THE 
                             PROPOSED TRANSACTION
                        -----------------------------



                                                       WASSERSTEIN PERELLA & CO.
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MYCOGEN CORPORATION                      BACKGROUND OF THE PROPOSED TRANSACTION
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TERMS OF DOW'S PROPOSAL

- -  THE DOW CHEMICAL COMPANY (TOGETHER WITH ITS AFFILIATES "DOW") HAS PROPOSED 
   ACQUIRING ALL OF THE OUTSTANDING SHARES OF MYCOGEN CORPORATION FOR CASH 
   CONSIDERATION OF $20.50 PER SHARE

- -  DOW'S $20.50 PER SHARE PRICE IMPLIES THE FOLLOWING MARKET CAPITALIZATION, 
   PREMIUM TO MARKET AND TRADING MULTIPLES




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            IMPLIED MARKET CAPITALIZATION ($ IN MM)
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Dow Offer Price                                                $20.50
Total Shares Outstanding                                        36.11
Total Options Outstanding                                        4.44
Average Strike Price of Options                                $12.03
                                                               ------
EQUITY MARKET VALUE                                           $777.81

Plus:  Net Debt(1)                                             $13.66
                                                               ------
ADJUSTED MARKET VALUE                                         $791.47
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- -----------------------------------------------------------------------------------------------------------------
                                ADJUSTED MARKET VALUE AS A MULTIPLE OF            MARKET VALUE AS A MULTIPLE OF
                                --------------------------------------            -----------------------------
                                SALES          EBITDA          EBIT               NET INCOME         BOOK VALUE
                                -----          ------          ----               ----------         ----------
                                                                                      
LTM BEFORE ADJ.(1)              3.7x             NM             NM                    NM                 3.7x
FY 1998 BEFORE ADJ.(2)          3.4x             NM             NM                    NM                 3.9x
FY 1999                         3.2x             NM             NM                    NM                 3.9x
- -----------------------------------------------------------------------------------------------------------------


- ---------------------------
(1) Includes other charges of $48.9MM (impairment of facilities and costs to 
    exit those facilities, severance, patent litigation fees, acquired 
    in-process technology and equity in net loss of investees)

(2) Includes projected litigation expenses of $11.0MM


                                                     WASSERSTEIN PERELLA & CO.
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MYCOGEN CORPORATION                      BACKGROUND OF THE PROPOSED TRANSACTION
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HISTORY OF DOW'S INVESTMENT IN MYCOGEN

- -  IN 1996, DOW ACQUIRED A 51.8% STAKE IN MYCOGEN

   -  On January 15, 1996, Dow agreed to acquire a 36.6% stake, or 
      approximately 9.5 million common shares of Mycogen from Lubrizol, for 
      roughly $13.26/share. In a simultaneous transaction, Dow acquired 
      approximately 4.5 million common shares of Mycogen in exchange for $26.5 
      million in cash and all of the outstanding shares of Dow's wholly-owned 
      subsidiary United AgriSeeds, Inc.

   -  On December 3, 1996, Dow acquired 1.0 million common shares of Mycogen 
      from Pioneer Hi-Bred International for $16.75/share

   -  During 1996, Dow acquired 850,000 common shares in open market 
      transactions at a weighted average price of $17.21/share


- -  IN 1997, DOW INCREASED ITS STAKE IN MYCOGEN TO 56.9%

   -  Dow acquired 2,287,843 common shares at a weighted average price of 
      $23.20/share

   -  Of these, 2,206,177 common shares (or 96%) were bought at prices in 
      excess of $20.50/share

   -  In connection with Dr. Caulder's resignation as Chairman of the Board 
      and CEO of Mycogen on May 1, 1997, Dow offered to purchase substantially 
      all shares of common stock owned by Dr. Caulder on the following terms

      -  $28.00/share for the number of shares equal to the sum of 30,000 plus 
         the number of shares issued to Dr. Caulder pursuant to his severance 
         agreement 

      -  All other shares would be purchased at a price equal to 105% of the 30 
         day trailing trading average of Mycogen stock

      -  Included in the 2,287,843 common shares referenced above were 95,752 
         common shares purchased by Dow from Dr. Caulder on May 2, 1997 at 
         $28.00/share


                                                     WASSERSTEIN PERELLA & CO.
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MYCOGEN CORPORATION                       BACKGROUND OF THE PROPOSED TRANSACTION
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HISTORY OF DOW'S INVESTMENT IN MYCOGEN (CONT'D)

- -  IN 1998, DOW INCREASED ITS STAKE IN MYCOGEN TO APPROXIMATELY 68.8%

   -  On January 9, 1998, Dow acquired 483,439 newly-issued common shares at 
      $19.46/share from Mycogen that were issued to finance Mycogen's 
      acquisition of an additional 16.25% stake in Verneuil Holdings S.A., a 
      French company

   -  On January 16, 1998, Dow purchased 3,762,038 newly-issued common shares 
      from Mycogen for $75 million cash, implying a share price of $19.94

   -  Dow purchased 296,035 common shares of Mycogen from Dr. Jerry L. 
      Caulder, former Chairman of Board and CEO of Mycogen, for $19.48/share

   -  On March 13, 1998, Dow agreed to purchase from Pioneer Overseas Corp. 
      2.0 million common shares of Mycogen for $20.06/share










                                                       WASSERSTEIN PERELLA & CO.
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MYCOGEN CORPORATION                       BACKGROUND OF THE PROPOSED TRANSACTION
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TERMS OF THE EXCHANGE AND PURCHASE AGREEMENT

- -  UNDER THE TERMS OF THE JANUARY 15, 1996 EXCHANGE AND PURCHASE AGREEMENT 
   (THE "AGREEMENT")

   -  Dow agreed, subject to certain limitations, that:

      -  Prior to February 19, 1998 (the second anniversary of the 
         "Measurement Date"), it would not acquire or propose to acquire 
         shares which, when aggregated with all other shares held by Dow 
         (other than shares acquired after February 19, 1996 directly from 
         Mycogen or any subsidiaries or employees) would constitute more than 
         60% of Mycogen's common stock

      -  Prior to February 19, 1999 (the third anniversary of the 
         "Measurement Date"), it would not acquire or propose to acquire 
         shares which, when aggregated with all other shares held by Dow (other 
         than shares acquired after February 19, 1996 directly from Mycogen 
         or any subsidiaries or employees) would constitute more than 65% of 
         Mycogen's common stock

   -  After February 19, 1999, Dow may acquire more than 79.9% of Mycogen's 
      outstanding shares only pursuant to a "Buyout Transaction"

      -  A "Buyout Transaction" is defined as a tender offer, merger or 
         similar transaction for "Third Party Sale Value"

      -  "Third Party Sale Value" is defined as the value that an 
         unaffiliated third party would be expected to pay in an arms'-length 
         transaction for all outstanding shares and share equivalents, NOT 
         TAKING INTO ACCOUNT DOW'S POTENTIALLY CONTROLLING POSITION

      -  A Buyout Transaction can be consummated only:

         -  With the approval of a majority of "Independent Directors" after 
            receipt of a fairness opinion from a recognized investment bank, 
            or

         -  If approval of a majority of the "Independent Directors" cannot 
            be obtained, through arbitration by an independent appraiser

   -  The Agreement may be amended only by a majority of the Independent 
      Directors and a majority of Mycogen's Board




                                                       WASSERSTEIN PERELLA & CO.
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MYCOGEN CORPORATION                       BACKGROUND OF THE PROPOSED TRANSACTION
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DISTRIBUTION OF VOLUME AT VARIOUS PRICES FOR THE LAST FIVE YEARS


THIS GRAPH ILLUSTRATES THE CUMULATIVE VOLUME OF MYCOGEN STOCK THAT TRADED AT 
VARIOUS PRICE INTERVALS OVER THE LAST FIVE YEARS.

                                               MYCO



Security Price History
MYCOGEN CORP. COM                                        17-Jul-98
MYCO          62845210    Common Stock                      NASDAQ          BAR             LINE
U.S. Dollar

     Date       Volume       High              Low           Close       Volume       Cumulative %
- ---------     --------    -------          -------         -------      -------      -------------
                                                                   
29-Dec-94       38,100     8.5000           8.0000          8.0000
27-Dec-94      104,800     9.0000           8.0000          8.0000
18-Jul-95       95,200     9.0000           8.0000          8.1250
03-Jan-95      111,100     8.5000           8.0000          8.1250
28-Dec-94       65,500     8.5000           8.0000          8.1250
21-Jul-95       25,600     8.7500           8.2500          8.2500
19-Jul-95       66,300     8.5000           7.7500          8.2500
30-Jun-95       21,800     8.7500           8.2500          8.2500
30-May-95       12,700     9.0000           8.2500          8.2500
25-May-95       86,400     9.0000           8.2500          8.2500
24-May-95       62,100     9.0000           8.1250          8.2500
23-May-95       61,500     9.0000           8.0000          8.2500
18-May-95       61,900     9.0000           8.2500          8.2500
04-Jan-95       45,000     8.5000           7.8750          8.2500
23-Dec-94       30,500     8.7500           8.2500          8.2500
22-Dec-94       31,100     8.7500           8.2500          8.2500
09-Dec-94       29,900     8.7500           8.1250          8.2500
06-Dec-94      101,600     9.2500           8.0000          8.2500
01-Jun-95       11,500     9.0000           8.2500          8.3750
31-May-95       11,200     9.0000           8.2500          8.3750
30-Dec-94      152,100     8.7500           8.0000          8.3750
08-Dec-94      133,400     9.0000           8.1250          8.3750
27-Jul-95       25,000     9.0000           8.5000          8.5000
26-Jul-95       31,700     9.0000           8.5000          8.5000
25-Jul-95       15,900     9.1250           8.5000          8.5000
20-Jul-95       16,600     8.7500           8.0000          8.5000
17-Jul-95       20,200     9.0000           8.5000          8.5000
14-Jul-95       34,600     9.0000           8.5000          8.5000
13-Jul-95       61,600     9.3750           8.5000          8.5000
03-Jul-95       11,900     9.0000           8.2500          8.5000
28-Jun-95       15,500     8.7500           8.2500          8.5000
27-Jun-95       59,300     9.2500           8.2500          8.5000
05-Jun-95        9,900     9.0000           8.5000          8.5000
02-Jun-95       23,700     9.0000           8.2500          8.5000
22-May-95       72,800     9.0000           8.2500          8.5000
21-Dec-94       83,500     8.7500           8.0000          8.5000
20-Dec-94       28,500     8.5000           8.0000          8.5000
19-Dec-94       55,900     8.5000           8.0000          8.5000
16-Dec-94       72,100     8.7500           8.2500          8.5000
14-Dec-94       50,100     9.0000           8.5000          8.5000
13-Dec-94       22,900     9.0000           8.5000          8.5000
02-Aug-95       35,900     9.0000           8.6250          8.6250
31-Jul-95       82,800     9.0000           8.5000          8.6250
17-May-95       19,400     9.2500           8.5000          8.6250
06-Jan-95       17,000     9.0000           8.6250          8.6250
15-Dec-94      182,200     9.0000           8.0000          8.6250
08-Aug-95       16,600     9.0000           8.7500          8.7500
04-Aug-95       31,900     9.0000           8.5000          8.7500
24-Jul-95       44,100     9.2500           8.2500          8.7500
12-Jul-95       13,300     9.5000           8.7500          8.7500
11-Jul-95       14,600     9.5000           8.7500          8.7500
06-Jul-95       81,100     9.1250           8.5000          8.7500
29-Jun-95       20,100     8.7500           8.2500          8.7500
26-Jun-95       43,200     9.2500           8.7500          8.7500
09-Jun-95       13,600     9.2500           8.7500          8.7500
12-Dec-94       18,400     9.0000           8.3750          8.7500
07-Dec-94       52,300     9.0000           8.2500          8.7500
01-Aug-95       43,300     9.0000           8.5000          8.8125
07-Jul-95       95,300     9.0000           8.5000          8.8750
15-May-95       47,400     9.2500           8.7500          8.8750
08-May-95       55,600     9.5000           8.8750          8.8750
09-Jan-95       22,800     9.1250           8.6250          8.8750
05-Jan-95       27,600     8.8750           8.2500          8.8750
07-Aug-95       46,600     9.0000           8.6250          9.0000
03-Aug-95       31,600     9.0000           8.2500          9.0000
28-Jul-95       35,000     9.0000           8.2500          9.0000
21-Jun-95       21,100     9.2500           8.7500          9.0000
16-Jun-95       42,000     9.2500           8.7500          9.0000
15-Jun-95        4,800     9.2500           8.7500          9.0000
14-Jun-95       70,900     9.2500           8.7500          9.0000
08-Jun-95       31,600     9.2500           8.7500          9.0000
07-Jun-95       48,700     9.0000           8.5000          9.0000
06-Jun-95       19,200     9.0000           8.5000          9.0000
26-May-95        5,500     9.0000           8.2500          9.0000
19-May-95       90,000     9.0000           8.2500          9.0000
16-May-95       33,700     9.0000           8.7500          9.0000
12-May-95       37,200     9.2500           8.8750          9.0000
10-May-95       40,900     9.5000           8.7500          9.0000
24-Mar-95       54,700    10.0000           9.0000          9.0000
19-Jun-95       44,300     9.5000           8.7500          9.0156
09-May-95       35,900     9.5000           8.8750          9.0625
20-Jun-95       34,200     9.2500           8.7500          9.1250
05-Dec-94       26,300     9.5000           8.7500          9.1250
15-Aug-95       56,400    10.2500           9.2500          9.2500
10-Jul-95       44,900     9.2500           8.6250          9.2500
05-Jul-95      109,900     9.2500           8.2500          9.2500
23-Jun-95       21,100     9.2500           8.7500          9.2500
22-Jun-95       38,000     9.2500           8.7500          9.2500
13-Jun-95       15,600     9.2500           8.7500          9.2500
12-Jun-95       13,600     9.5000           8.7500          9.2500
11-May-95        5,900     9.2500           8.8750          9.2500
04-May-95       38,800     9.6250           9.0000          9.2500
28-Apr-95       25,400    10.0000           9.2500          9.2500
21-Apr-95       25,100     9.7500           9.2500          9.2500
28-Feb-95       42,600    10.0000           9.2500          9.2500
02-Dec-94       33,600     9.7500           9.2500          9.2500
01-Dec-94       21,700    10.0000           9.2500          9.2500
28-Nov-94       26,700     9.7500           9.2500          9.2500
31-Mar-94       29,000    10.0000           9.2500          9.2500
09-Mar-94       37,600    10.0000           9.2500          9.2500
30-Mar-95       26,500    10.0000           9.2500          9.3750
21-Mar-95      260,700    10.2500           8.7500          9.3750
10-Jan-95       80,400    10.2500           9.0000          9.3750
22-Nov-94       23,600    10.0000           9.3750          9.3750
18-Aug-95       31,200     9.7500           9.2500          9.5000
05-May-95        3,400     9.5000           9.0000          9.5000
02-May-95       26,700     9.7500           9.2500          9.5000
27-Apr-95       16,300    10.0000           9.5000          9.5000
26-Apr-95       34,600    10.0000           9.2500          9.5000
20-Apr-95       57,100    10.2500           9.2500          9.5000
19-Apr-95       19,900    10.2500           9.5000          9.5000
07-Apr-95        9,800    10.2500           9.5000          9.5000
27-Mar-95       19,300    10.0000           9.0000          9.5000
22-Mar-95       59,600    10.0000           8.7500          9.5000
17-Mar-95       11,700    10.0000           9.5000          9.5000
15-Mar-95        8,900    10.0000           9.5000          9.5000
09-Mar-95       55,300    10.2500           9.5000          9.5000
29-Nov-94       23,300     9.7500           9.2500          9.5000
23-Nov-94       44,900     9.7500           9.2500          9.5000
21-Nov-94       17,500    10.0000           9.5000          9.5000
19-Apr-94       94,000    10.5000           9.5000          9.5000
15-Apr-94        3,800    10.2500           9.5000          9.5000
13-Apr-94        7,100    10.2500           9.5000          9.5000
04-Apr-94       16,600    10.0000           9.2500          9.5000
01-May-95       13,000     9.7500           9.2500          9.5313
16-Aug-95       42,700    10.0000           9.0000          9.6250
09-Aug-95      123,100     9.6250           8.7500          9.6250
29-Mar-95       19,900    10.0000           9.2500          9.6250
10-Mar-94       51,500     9.7500           9.2500          9.6250
13-Sep-95       39,900    10.1250           9.7500          9.7500
21-Aug-95       30,800     9.7500           9.2500          9.7500
17-Aug-95       14,400     9.7500           9.2500          9.7500
14-Aug-95      150,100    10.2500           9.7500          9.7500
03-May-95       14,500     9.7500           9.2500          9.7500
25-Apr-95       16,700     9.7500           9.2500          9.7500
24-Apr-95       10,700     9.7500           9.2500          9.7500
05-Apr-95       59,500    10.0000           9.5000          9.7500
04-Apr-95       27,400    10.0000           9.2500          9.7500
03-Apr-95       17,800     9.7500           9.2500          9.7500
31-Mar-95       16,300     9.7500           9.2500          9.7500
07-Mar-95       15,600    10.2500           9.5000          9.7500
06-Mar-95       20,500    10.2500           9.7500          9.7500
27-Feb-95       14,200    10.0000           9.2500          9.7500
23-Feb-95       93,800    10.2500           9.2500          9.7500
19-Jan-95       86,200    10.2500           9.5000          9.7500
25-Nov-94        8,500     9.7500           9.2500          9.7500
17-Nov-94       15,900    10.1250           9.6250          9.7500
16-Nov-94       36,700    10.1250           9.7500          9.7500
21-Oct-94        2,700    10.5000           9.7500          9.7500
22-Aug-94       22,600    10.2500           9.7500          9.7500
10-Aug-94       11,400    10.2500           9.7500          9.7500
09-Aug-94       19,200    10.3125           9.7500          9.7500
11-Mar-94       20,700     9.7500           9.2500          9.7500
07-Mar-94       44,000    10.2500           9.7500          9.7500
27-Dec-93       42,400    10.2500           9.5000          9.7500
10-Dec-93       56,600    10.2500           9.7500          9.7500
09-Dec-93       31,800    10.2500           9.7500          9.7500
03-Dec-93       88,900    10.2500           9.7500          9.7500
19-Aug-94        8,000    10.2500           9.7500          9.8125
25-Aug-95       12,800    10.2500           9.5000          9.8750
08-Mar-95       25,100    10.2500           9.5000          9.8750
15-Nov-94       79,700    10.2500           9.8750          9.8750
14-Nov-94       17,700    10.2500           9.8750          9.8750
11-Nov-94        4,500    10.2500           9.8750          9.8750
09-Nov-94      213,000    10.5000           9.8750          9.8750
01-Nov-94       35,200    10.5000           9.7500          9.8750
05-Aug-94       32,400    10.5000           9.7500          9.8750
22-Jul-94       96,700    10.2500           9.7500          9.8750
04-Mar-94       43,800    10.2500           9.7500          9.8750
21-Jul-94       80,600    10.2500           9.7500          9.9375
12-Sep-95       60,600    10.1250           9.7500         10.0000
06-Sep-95       27,700    10.1250           9.5000         10.0000
05-Sep-95       42,900    10.2500           9.5000         10.0000
28-Aug-95      111,200    10.2500           9.5000         10.0000
24-Aug-95       20,600    10.2500           9.5000         10.0000
23-Aug-95       23,100    10.2500           9.5000         10.0000
22-Aug-95       29,900    10.2500           9.3750         10.0000
18-Apr-95       17,700    10.2500           9.5000         10.0000
17-Apr-95      222,600    10.2500           9.5000         10.0000
13-Apr-95       29,400    10.2500           9.5000         10.0000
11-Apr-95       17,000    10.2500           9.5000         10.0000
10-Apr-95       22,400    10.2500           9.5000         10.0000
28-Mar-95        9,400    10.0000           9.2500         10.0000
23-Mar-95       23,900    10.0000           9.5000         10.0000
16-Mar-95        9,200    10.0000           9.5000         10.0000
14-Mar-95       17,000    10.2500           9.5000         10.0000
02-Mar-95       36,900    10.0000           9.5000         10.0000
01-Mar-95       36,000    10.0000           9.2500         10.0000
24-Feb-95       28,900    10.0000           9.5000         10.0000
30-Nov-94       17,200    10.0000           9.5000         10.0000
18-Nov-94       23,000    10.1250           9.5000         10.0000
10-Nov-94       76,000    10.2500           9.8750         10.0000
08-Nov-94       18,800    10.2500          10.0000         10.0000
04-Nov-94       20,900    10.5000          10.0000         10.0000
31-Oct-94       15,500    10.5000          10.0000         10.0000
26-Oct-94       40,300    10.5000           9.7500         10.0000
25-Oct-94       54,600    10.2500           9.5000         10.0000
24-Oct-94       17,500    10.5000           9.7500         10.0000
17-Oct-94       13,400    10.5000          10.0000         10.0000
11-Oct-94       17,600    10.5000           9.7500         10.0000
07-Oct-94       58,400    10.5000          10.0000         10.0000
06-Oct-94       22,200    10.5000          10.0000         10.0000
03-Oct-94       10,800    10.5000          10.0000         10.0000
30-Sep-94        6,400    10.5000          10.0000         10.0000
29-Sep-94       29,200    10.5000          10.0000         10.0000
26-Sep-94       18,200    10.2500           9.7500         10.0000
23-Sep-94       33,200    10.5000          10.0000         10.0000
22-Sep-94       49,500    10.5000          10.0000         10.0000
21-Sep-94        9,800    10.5000          10.0000         10.0000
20-Sep-94       22,500    10.5000          10.0000         10.0000
16-Sep-94        3,400    10.5000          10.0000         10.0000
14-Sep-94       13,300    10.5000          10.0000         10.0000
12-Sep-94       28,800    10.2500          10.0000         10.0000
08-Sep-94        7,600    10.2500          10.0000         10.0000
07-Sep-94       50,100    10.5000          10.0000         10.0000
06-Sep-94        5,600    10.5000          10.0000         10.0000
02-Sep-94       21,100    10.5000          10.0000         10.0000
01-Sep-94       17,700    10.5000          10.0000         10.0000
29-Aug-94       20,100    10.5000          10.0000         10.0000
26-Aug-94       23,100    10.5000          10.0000         10.0000
18-Aug-94       25,600    10.5000           9.7500         10.0000
12-Aug-94       34,300    10.5000          10.0000         10.0000
04-Aug-94       12,700    10.5000          10.0000         10.0000
03-Aug-94       10,500    10.5000          10.0000         10.0000
02-Aug-94        7,300    10.5000          10.0000         10.0000
01-Aug-94       10,400    10.5000          10.0000         10.0000
29-Jul-94       59,600    10.5000          10.0000         10.0000
28-Jul-94       13,900    10.5000          10.0000         10.0000
25-Jul-94       38,900    10.0000           9.7500         10.0000
15-Jul-94       75,100    10.7500          10.0000         10.0000
12-Apr-94       46,600    11.0000           9.5000         10.0000
30-Mar-94       21,500    10.0000           9.2500         10.0000
08-Mar-94       43,300    10.2500           9.5000         10.0000
03-Mar-94       49,000    10.2500           9.8750         10.0000
30-Dec-93       76,400    10.5000          10.0000         10.0000
29-Dec-93       70,100    10.5000          10.0000         10.0000
28-Dec-93      109,200    10.2500           9.7500         10.0000
23-Dec-93       45,000    10.0000           9.5000         10.0000
22-Dec-93       35,900    10.5000           9.5000         10.0000
21-Dec-93       40,900    10.5000          10.0000         10.0000
07-Nov-94       42,100    10.2500          10.0000         10.0625
28-Oct-94       14,200    10.5000          10.0000         10.0625
15-Sep-95      342,500    10.2500           9.5000         10.1250
14-Sep-95       76,800    10.1250           9.7500         10.1250
11-Sep-95       98,400    10.1250           9.8750         10.1250
08-Sep-95       32,500    10.1250           9.8750         10.1250
07-Sep-95       87,900    10.1250           9.6250         10.1250
20-Jan-95       49,600    10.1250           9.6250         10.1250
18-Jan-95       27,300    10.5000          10.1250         10.1250
03-Nov-94       26,500    10.5000          10.0000         10.1250
02-Nov-94       24,400    10.2500           9.7500         10.1250
20-Oct-94       12,700    10.2500           9.7500         10.1250
30-Aug-94       60,200    10.5000          10.0000         10.1250
16-Aug-94       20,300    10.2500           9.7500         10.1250
02-Mar-94       25,100    10.5000           9.7500         10.1250
13-Dec-93      153,000    10.2500           9.5000         10.1250
01-Sep-95       13,000    10.2500           9.5000         10.2500
31-Aug-95       34,300    10.2500           9.5000         10.2500
30-Aug-95       10,700    10.2500           9.5000         10.2500
29-Aug-95        9,300    10.2500           9.5000         10.2500
11-Aug-95      107,800    11.0000           9.7500         10.2500
10-Aug-95      219,300    11.2500          10.2500         10.2500
12-Apr-95       27,700    10.2500           9.7500         10.2500
06-Apr-95       42,500    10.2500           9.2500         10.2500
13-Mar-95       11,400    10.2500           9.5000         10.2500
10-Mar-95        7,700    10.2500           9.5000         10.2500
03-Mar-95       19,000    10.2500           9.5000         10.2500
22-Feb-95       87,300    10.2500           9.7500         10.2500
21-Feb-95      231,700    11.5000           9.5000         10.2500
11-Jan-95      152,400    10.2500           9.6250         10.2500
27-Oct-94       27,900    10.5000          10.0000         10.2500
19-Oct-94       14,300    10.5000           9.7500         10.2500
13-Oct-94       11,100    10.5000          10.0000         10.2500
12-Oct-94        8,000    10.2500           9.7500         10.2500
04-Oct-94       99,300    10.5000          10.2500         10.2500
27-Sep-94       20,900    10.2500           9.7500         10.2500
09-Sep-94       14,500    10.2500          10.0000         10.2500
23-Aug-94       28,700    10.5000           9.7500         10.2500
15-Aug-94        7,900    10.2500          10.0000         10.2500
11-Aug-94       46,100    10.2500           9.7500         10.2500
08-Aug-94       17,100    10.2500           9.5000         10.2500
20-Jul-94      159,300    10.2500           9.7500         10.2500
19-Jul-94      107,600    10.5000           9.7500         10.2500
14-Jul-94       85,100    10.7500          10.2500         10.2500
13-Jul-94        2,700    10.7500          10.2500         10.2500
27-May-94       16,600    10.7500          10.2500         10.2500
26-May-94        7,300    10.7500          10.2500         10.2500
23-May-94       20,300    10.7500          10.2500         10.2500
21-Apr-94      153,100    11.5000           9.7500         10.2500
20-Apr-94       71,600    10.2500           9.5000         10.2500
14-Apr-94        9,900    10.2500           9.5000         10.2500
29-Mar-94       17,200    10.7500           9.7500         10.2500
25-Mar-94       23,400    11.0000          10.2500         10.2500
24-Mar-94       45,200    11.0000          10.2500         10.2500
31-Dec-93       64,700    10.7500          10.0000         10.2500
20-Dec-93       54,900    10.7500          10.0000         10.2500
16-Dec-93       50,500    10.5000          10.0000         10.2500
08-Dec-93       22,600    10.2500           9.7500         10.2500
07-Dec-93      118,400    10.2500           9.7500         10.2500
06-Dec-93       54,400    10.2500           9.5000         10.2500
02-Dec-93       49,000    10.2500           9.7500         10.2500
01-Dec-93       43,900    10.2500           9.7500         10.2500
30-Nov-93      114,500    10.2500           9.7500         10.2500
29-Nov-93      101,300    10.7500           9.7500         10.2500
23-Nov-93       40,700    10.5000          10.0000         10.2500
19-Sep-94       15,200    10.5000          10.0000         10.3750
11-Jul-94       11,800    10.7500          10.2500         10.3750
28-Mar-94        5,400    11.0000          10.2500         10.3750
14-Mar-94       29,500    10.5000           9.2500         10.3750
22-Nov-93       70,400    11.0000          10.0000         10.3750
20-Mar-95       42,600    10.7500          10.0000         10.5000
23-Jan-95       56,700    10.5000           9.6250         10.5000
17-Jan-95       47,400    11.3750          10.2500         10.5000
18-Oct-94       12,700    10.5000           9.7500         10.5000
14-Oct-94       13,200    10.5000          10.0000         10.5000
10-Oct-94        4,400    10.5000          10.0000         10.5000
05-Oct-94       22,900    10.5000          10.2500         10.5000
28-Sep-94       21,300    10.5000          10.0000         10.5000
15-Sep-94       26,000    10.5000          10.0000         10.5000
13-Sep-94       20,500    10.5000          10.0000         10.5000
31-Aug-94       35,300    10.5000          10.1250         10.5000
25-Aug-94       27,500    10.5000          10.0000         10.5000
24-Aug-94       13,800    10.5000          10.0000         10.5000
17-Aug-94       36,700    10.5000          10.0000         10.5000
27-Jul-94       27,700    11.0000          10.0000         10.5000
18-Jul-94      105,400    10.5000           9.7500         10.5000
07-Jul-94       28,100    11.0000          10.2500         10.5000
31-May-94       46,200    11.0000          10.5000         10.5000
25-May-94       34,500    10.7500          10.2500         10.5000
16-May-94        7,900    11.0000          10.5000         10.5000
18-Apr-94      203,600    10.5000           9.5000         10.5000
06-Apr-94       38,400    10.5000          10.0000         10.5000
05-Apr-94       18,000    10.5000           9.5000         10.5000
23-Mar-94       14,800    11.0000          10.5000         10.5000
18-Mar-94       25,600    11.2500          10.5000         10.5000
25-Feb-94       15,200    11.0000          10.5000         10.5000
24-Feb-94       45,400    11.0000          10.5000         10.5000
23-Feb-94       13,000    11.0000          10.5000         10.5000
17-Dec-93       19,000    10.5000          10.0000         10.5000
15-Dec-93       34,100    10.5000          10.0000         10.5000
14-Dec-93       87,700    10.5000           9.7500         10.5000
26-Nov-93        2,900    10.5000          10.0000         10.5000
24-Nov-93       20,100    10.5000          10.0000         10.5000
19-Nov-93       32,600    11.0000          10.5000         10.5000
18-Nov-93       11,600    11.0000          10.5000         10.5000
26-Jul-94       33,200    11.0000          10.2500         10.5625
13-May-94       41,800    11.0000          10.5000         10.6250
16-Mar-94       35,000    11.0000          10.5000         10.6250
03-Jan-94       31,600    10.7500          10.2500         10.6250
16-Jan-95       62,200    11.8750          10.7500         10.7500
12-Jul-94        6,500    10.7500          10.2500         10.7500
08-Jul-94       11,100    10.7500          10.2500         10.7500
06-Jul-94       30,800    11.2500          10.5000         10.7500
05-Jul-94        7,700    11.2500          10.7500         10.7500
30-Jun-94        9,000    11.5000          10.7500         10.7500
28-Jun-94       13,300    11.2500          10.7500         10.7500
27-Jun-94       14,400    11.2500          10.7500         10.7500
24-May-94       24,500    10.7500          10.2500         10.7500
20-May-94       99,000    11.2500          10.5000         10.7500
18-May-94        4,500    11.2500          10.7500         10.7500
17-May-94       32,600    11.2500          10.5000         10.7500
12-May-94       18,200    11.2500          10.5000         10.7500
22-Mar-94        5,300    11.0000          10.5000         10.7500
21-Mar-94       14,900    11.0000          10.5000         10.7500
01-Mar-94      645,300    11.0000          10.2500         10.7500
18-Feb-94       46,900    11.2500          10.5000         10.7500
17-Feb-94       22,800    11.7500          10.7500         10.7500
04-Jan-94       39,500    11.0000          10.5000         10.7500
16-Nov-93        9,700    11.2500          10.7500         10.7500
04-Nov-93       21,700    11.5000          10.7500         10.7500
25-Oct-93      175,400    11.5000          10.2500         10.7500
30-Jan-95       49,400    11.5000          10.8750         10.8750
11-May-94       51,200    11.7500          10.5000         10.8750
15-Mar-94       46,600    11.0000          10.2500         10.8750
15-Nov-93       13,300    11.5000          10.7500         10.8750
12-Jan-95      172,800    11.1250           9.8750         11.0000
01-Jul-94       25,900    11.2500          10.7500         11.0000
29-Jun-94        3,400    11.2500          10.7500         11.0000
20-Jun-94       15,500    11.2500          11.0000         11.0000
17-Jun-94        9,900    11.5000          11.0000         11.0000
07-Jun-94       16,900    11.5000          10.7500         11.0000
02-Jun-94       10,900    11.0000          10.2500         11.0000
01-Jun-94        2,300    11.0000          10.2500         11.0000
22-Apr-94      436,900    11.2500          10.0000         11.0000
11-Apr-94       28,200    11.2500          10.5000         11.0000
07-Apr-94       39,400    11.0000          10.2500         11.0000
28-Feb-94       22,200    11.0000          10.5000         11.0000
22-Feb-94       29,100    11.0000          10.5000         11.0000
17-Nov-93       29,500    11.2500          10.5000         11.0000
12-Nov-93       10,000    11.5000          11.0000         11.0000
11-Nov-93       13,100    11.5000          11.0000         11.0000
08-Nov-93       10,200    11.0000          10.7500         11.0000
05-Nov-93       43,300    11.0000          10.5000         11.0000
03-Nov-93       16,500    11.5000          11.0000         11.0000
02-Nov-93       19,100    11.5000          11.0000         11.0000
26-Jan-95       53,300    11.6250          11.1250         11.1250
25-Jan-95       54,500    11.6250          11.0000         11.1250
06-Jun-94       21,500    11.2500          10.7500         11.1250
01-Nov-93       10,000    11.5000          11.0000         11.1250
27-Jan-95       20,600    11.5000          11.0000         11.2500
24-Jun-94       23,100    11.2500          10.7500         11.2500
21-Jun-94        9,500    11.2500          11.0000         11.2500
15-Jun-94       39,700    12.0000          11.0000         11.2500
08-Jun-94       24,700    11.5000          11.0000         11.2500
03-Jun-94       20,500    11.2500          10.5000         11.2500
19-May-94       98,700    11.2500          10.7500         11.2500
29-Apr-94       37,500    11.5000          11.2500         11.2500
08-Apr-94       72,100    11.2500          10.5000         11.2500
17-Mar-94       27,600    11.2500          10.5000         11.2500
14-Feb-94       38,200    11.7500          11.0000         11.2500
11-Feb-94       10,800    11.7500          11.2500         11.2500
10-Feb-94       43,800    11.5000          11.2500         11.2500
08-Feb-94       67,700    11.7500          11.2500         11.2500
19-Jan-94       64,000    11.5000          11.0000         11.2500
10-Nov-93       15,100    11.5000          10.7500         11.2500
29-Oct-93       52,100    11.5000          11.0000         11.2500
22-Oct-93       15,200    11.7500          11.2500         11.2500
29-Sep-93       32,400    11.7500          11.2500         11.2500
28-Sep-93       45,000    11.7500          11.2500         11.2500
22-Jul-93       37,500    12.0000          11.2500         11.2500
01-Feb-95       30,500    11.5000          11.0000         11.3750
31-Jan-95       38,700    11.3750          10.7500         11.3750
09-Jun-94       17,400    11.5000          10.7500         11.3750
28-Apr-94       69,100    11.5000          11.2500         11.3750
25-Apr-94      202,400    11.5000          10.7500         11.3750
07-Feb-94       33,600    11.7500          11.2500         11.3750
21-Oct-93       19,200    12.0000          11.3750         11.3750
22-Sep-93       24,400    11.5000          11.0000         11.3750
18-Sep-95      223,700    11.5000          10.0000         11.5000
14-Feb-95      100,400    11.7500          11.5000         11.5000
06-Feb-95       17,500    11.7500          11.0000         11.5000
24-Jan-95      166,900    11.7500          10.5000         11.5000
23-Jun-94        9,800    11.5000          11.0000         11.5000
22-Jun-94       20,600    11.5000          11.0000         11.5000
16-Jun-94        7,400    11.7500          11.0000         11.5000
13-Jun-94       16,600    11.7500          11.2500         11.5000
10-Jun-94       17,000    11.7500          11.0000         11.5000
09-May-94       23,900    11.7500          11.2500         11.5000
26-Apr-94       35,700    11.5000          11.2500         11.5000
15-Feb-94       22,800    11.5000          11.0000         11.5000
09-Feb-94       12,600    11.5000          11.2500         11.5000
03-Feb-94       22,700    12.0000          11.5000         11.5000
02-Feb-94       16,300    12.0000          11.5000         11.5000
27-Jan-94       42,500    11.7500          11.5000         11.5000
26-Jan-94       24,100    11.7500          11.2500         11.5000
25-Jan-94       23,500    11.7500          11.2500         11.5000
24-Jan-94       19,500    11.7500          11.5000         11.5000
21-Jan-94       24,600    11.7500          11.5000         11.5000
14-Jan-94        9,200    12.0000          11.5000         11.5000
13-Jan-94       19,600    12.0000          11.5000         11.5000
10-Jan-94       18,400    12.0000          11.5000         11.5000
06-Jan-94       42,900    12.0000          11.5000         11.5000
09-Nov-93       14,700    11.5000          10.7500         11.5000
28-Oct-93       64,800    12.0000          11.2500         11.5000
27-Oct-93       68,300    12.0000          11.0000         11.5000
26-Oct-93       22,400    11.5000          10.7500         11.5000
27-Sep-93       47,600    11.7500          11.5000         11.5000
23-Sep-93       32,700    11.5000          11.2500         11.5000
21-Sep-93       54,100    12.0000          11.0000         11.5000
23-Jul-93       37,500    11.7500          11.0000         11.5000       20,015,600   0.281849
06-May-94       11,700    11.7500          11.2500         11.5625
17-Feb-95       47,400    12.0000          11.5000         11.6250
10-Feb-95       24,700    11.7500          11.5000         11.6250
13-Jan-95      103,900    11.8750          10.8750         11.6250
14-Jun-94       24,500    12.0000          11.5000         11.6250
31-Jan-94       10,800    11.7500          11.2500         11.6250
16-Feb-95       35,400    12.0000          11.5000         11.6875
13-Feb-95       70,200    12.0000          11.5000         11.7500
09-Feb-95       33,600    11.8750          11.5000         11.7500
08-Feb-95       21,600    11.8750          11.5000         11.7500
07-Feb-95       30,400    12.0000          11.1250         11.7500
03-Feb-95       18,700    11.8750          11.3750         11.7500
02-Feb-95       34,800    11.7500          11.1250         11.7500
10-May-94       16,300    11.7500          11.2500         11.7500
05-May-94       28,700    11.7500          11.2500         11.7500
04-May-94       14,900    11.7500          11.2500         11.7500
03-May-94       32,600    11.7500          11.2500         11.7500
02-May-94       61,700    11.7500          11.2500         11.7500
16-Feb-94       54,600    11.7500          11.0000         11.7500
04-Feb-94       17,900    12.0000          11.5000         11.7500
01-Feb-94       44,700    11.7500          11.2500         11.7500
28-Jan-94       22,500    11.7500          11.2500         11.7500
20-Jan-94       52,900    11.7500          11.0000         11.7500
18-Jan-94       20,300    12.0000          11.2500         11.7500
15-Oct-93        9,400    12.2500          11.7500         11.7500
13-Oct-93      193,200    12.5000          11.7500         11.7500
24-Sep-93       56,200    11.7500          11.0000         11.7500
20-Sep-93       10,400    12.0000          11.5000         11.7500
26-Jul-93       65,300    12.0000          11.5000         11.7500
07-Jan-94       33,800    12.0000          11.5000         11.8750
17-Sep-93       30,700    12.0000          11.5000         11.8750
20-Jul-93       30,300    12.2500          11.7500         11.8750
16-Jul-93       25,600    12.2500          11.7500         11.8750
07-Dec-95       51,500    12.2500          11.7500         12.0000
15-Feb-95       13,700    12.0000          11.5000         12.0000
17-Jan-94       21,100    12.0000          11.5000         12.0000
12-Jan-94        9,400    12.0000          11.5000         12.0000
11-Jan-94       13,500    12.0000          11.5000         12.0000
05-Jan-94       54,800    12.0000          11.2500         12.0000
20-Oct-93       43,000    12.0000          11.5000         12.0000
19-Oct-93       34,100    12.5000          12.0000         12.0000
14-Oct-93       21,000    12.2500          11.7500         12.0000
06-Dec-95       58,500    12.7500          11.7500         12.1250
27-Jul-93       88,200    12.2500          11.7500         12.1250
11-Dec-95       49,200    12.5000          11.8750         12.2500
08-Dec-95       13,600    12.2500          11.8750         12.2500
12-Oct-93       11,500    12.7500          12.2500         12.2500
11-Oct-93        4,800    12.7500          12.2500         12.2500
16-Sep-93       18,300    12.2500          11.7500         12.2500
15-Sep-93       50,700    12.7500          11.7500         12.2500
14-Sep-93       19,100    12.7500          12.2500         12.2500
16-Aug-93       23,100    12.7500          12.2500         12.2500
13-Aug-93       19,600    12.5000          12.2500         12.2500
12-Aug-93       11,200    12.5000          12.2500         12.2500
11-Aug-93        4,800    12.5000          12.2500         12.2500
10-Aug-93       12,900    12.5000          12.2500         12.2500
05-Aug-93       13,400    12.7500          12.2500         12.2500
21-Jul-93       71,300    12.2500          11.7500         12.2500
19-Jul-93       36,900    12.2500          11.7500         12.2500
05-Dec-95       56,800    13.0000          12.2500         12.5000
01-Dec-95       46,300    13.1250          12.5000         12.5000
27-Nov-95       19,800    13.1250          12.5000         12.5000
14-Nov-95       16,300    12.8750          12.2500         12.5000
09-Nov-95       19,000    13.1250          12.3750         12.5000
21-Sep-95      142,100    13.2500          12.5000         12.5000
18-Oct-93       25,700    12.5000          11.7500         12.5000
07-Oct-93       10,900    13.0000          12.5000         12.5000
06-Oct-93       48,700    13.0000          12.5000         12.5000
13-Sep-93       22,200    13.0000          12.5000         12.5000
10-Sep-93       11,900    13.0000          12.5000         12.5000
09-Sep-93       36,600    13.5000          12.5000         12.5000
18-Aug-93      336,000    13.2500          12.5000         12.5000
09-Aug-93       15,900    12.5000          12.0000         12.5000
04-Aug-93       26,000    12.7500          12.2500         12.5000
03-Aug-93       55,400    12.7500          12.5000         12.5000
02-Aug-93       52,200    12.7500          12.5000         12.5000
28-Jul-93       81,900    12.5000          12.2500         12.5000
16-Nov-95       14,000    12.6250          12.2500         12.6250
15-Nov-95        8,700    12.7500          12.2500         12.6250
05-Oct-93       45,900    13.2500          12.5000         12.6250
04-Dec-95       29,400    13.0000          12.5000         12.7500
17-Nov-95        8,000    12.7500          12.2500         12.7500
27-Oct-95       33,300    13.2500          12.7500         12.7500
08-Oct-93       12,300    13.0000          12.2500         12.7500
04-Oct-93      197,600    13.2500          12.7500         12.7500
30-Sep-93       73,300    13.0000          11.2500         12.7500
06-Aug-93       54,000    12.7500          12.2500         12.7500
30-Jul-93       53,000    12.7500          12.2500         12.7500
29-Jul-93       29,100    12.7500          12.2500         12.7500
24-Nov-95        2,900    13.1250          12.8750         12.8750
21-Nov-95       26,600    13.2500          12.8750         12.8750
08-Nov-95       29,800    13.1250          12.8750         12.8750
03-Nov-95       13,200    13.3750          12.7500         12.8750
25-Oct-95       93,000    13.7500          12.6250         12.8750
09-Oct-95       67,900    13.5000          12.8750         12.8750
25-Sep-95       61,300    13.5000          12.5000         12.8750
22-Nov-95       13,000    13.2500          12.8750         13.0000
20-Nov-95       55,400    13.2500          12.5000         13.0000
13-Nov-95        8,500    13.0000          12.5000         13.0000
10-Nov-95       16,500    13.0000          12.5000         13.0000
07-Nov-95       19,200    13.2500          12.7500         13.0000
02-Nov-95        9,700    13.3750          12.7500         13.0000
10-Oct-95       81,000    13.0000          12.7500         13.0000
22-Sep-95       45,400    13.0000          12.5000         13.0000
20-Sep-95      279,700    13.7500          12.7500         13.0000
08-Sep-93       34,100    13.5000          12.7500         13.0000
02-Sep-93        8,300    13.5000          13.0000         13.0000
01-Sep-93       18,100    13.5000          13.0000         13.0000
30-Aug-93       32,000    13.5000          13.0000         13.0000
27-Aug-93       16,900    13.5000          13.0000         13.0000
24-Aug-93       26,500    13.2500          12.7500         13.0000
23-Aug-93       47,800    13.2500          12.5000         13.0000
20-Aug-93       26,800    13.2500          12.7500         13.0000
17-Aug-93      177,800    13.0000          12.5000         13.0000
30-Nov-95       11,200    13.1250          12.7500         13.1250
29-Nov-95        8,300    13.1250          12.7500         13.1250
28-Nov-95       11,600    13.1250          12.5000         13.1250
01-Nov-95       18,000    13.3750          12.7500         13.1250
30-Oct-95       54,600    13.2500          12.7500         13.1250
17-Oct-95       23,500    13.6250          13.1250         13.1250
16-Oct-95       31,400    13.5000          13.1250         13.1250
13-Oct-95       10,100    13.5000          13.1250         13.1250
07-Sep-93       47,500    13.5000          13.0000         13.1250
19-Aug-93       39,500    13.2500          12.5000         13.1250
06-Nov-95       29,500    13.2500          12.8750         13.2500
26-Oct-95       46,800    13.2500          12.7500         13.2500
19-Oct-95       14,900    13.7500          13.1250         13.2500
19-Sep-95      560,900    13.6250          11.0000         13.2500
01-Oct-93       36,800    13.2500          12.7500         13.2500
31-Aug-93       60,500    13.5000          13.0000         13.2500
26-Aug-93       46,300    13.5000          12.7500         13.2500
25-Aug-93       29,800    13.2500          12.7500         13.2500
12-Dec-95      166,200    13.7500          12.2500         13.3750
31-Oct-95        6,400    13.3750          12.7500         13.3750
18-Oct-95       37,900    13.7500          13.1250         13.3750
11-Oct-95       67,600    13.5000          13.0000         13.3750
06-Oct-95       30,100    13.6250          13.3750         13.3750
12-Jul-96       22,000    14.0000          13.1250         13.5000
15-Dec-95       50,000    14.0000          13.5000         13.5000
24-Oct-95       21,500    14.0000          13.5000         13.5000
23-Oct-95       19,800    14.0000          13.5000         13.5000
12-Oct-95       54,100    13.5000          13.1250         13.5000
05-Oct-95      100,600    13.6250          13.3750         13.5000
04-Oct-95       54,600    13.7500          13.5000         13.5000
03-Sep-93        8,300    13.5000          13.0000         13.5000
03-Oct-95      118,600    13.8750          13.5000         13.6250
27-Sep-95      137,700    14.0000          13.3750         13.6250
11-Jul-96       29,300    14.2500          13.2500         13.7500
14-Dec-95       99,100    14.1250          13.5000         13.7500
29-Sep-95       33,700    14.0000          13.6250         13.7500
13-Dec-95       59,200    14.0000          13.2500         13.8125
21-Dec-95       96,800    14.2500          13.8750         13.8750
20-Dec-95      107,500    14.5000          13.8750         13.8750
18-Dec-95       68,900    14.0000          13.5000         13.8750
02-Oct-95       78,000    14.2500          13.5000         13.8750
17-Sep-96       27,000    14.5000          14.0000         14.0000
16-Sep-96      127,600    14.2500          13.7500         14.0000
12-Sep-96       71,700    15.5000          13.7500         14.0000
10-Jul-96       85,400    14.7500          13.0000         14.0000
28-Sep-95       58,400    14.0000          13.6250         14.0000
26-Sep-95      179,200    14.0000          13.3750         14.0000
20-Oct-95      104,900    14.1250          13.2500         14.1250
22-Oct-96        9,500    14.5000          14.2500         14.2500
21-Oct-96       29,400    14.5000          14.2500         14.2500
18-Oct-96       20,200    14.5000          14.2500         14.2500
16-Oct-96       84,600    14.5000          14.2500         14.2500
15-Oct-96       23,700    14.5000          14.2500         14.2500
14-Oct-96       33,800    14.5000          14.2500         14.2500
11-Oct-96       96,500    14.5000          14.2500         14.2500
09-Oct-96      147,600    14.7500          14.0000         14.2500
04-Oct-96       18,500    15.0000          14.2500         14.2500
03-Oct-96        1,600    15.0000          14.2500         14.2500
30-Sep-96       23,200    15.0000          14.2500         14.2500
23-Sep-96       21,300    14.7500          14.2500         14.2500
20-Sep-96       13,100    14.7500          14.2500         14.2500
18-Sep-96       95,600    14.7500          14.0000         14.2500
13-Sep-96       40,000    14.7500          13.7500         14.2500
15-Jul-96      101,600    14.6250          13.7500         14.2500
08-Jan-96       63,800    14.6250          13.6250         14.2500
19-Dec-95      110,000    14.5000          13.8750         14.2500
10-Oct-96       29,500    14.5000          14.2500         14.3750
08-Oct-96       28,000    14.7500          14.2500         14.3750
17-Oct-96       14,000    14.5000          14.2500         14.4750
27-Sep-96       13,100    15.0000          14.2500         14.5000
25-Sep-96       20,400    14.7500          14.2500         14.5000
24-Sep-96       27,900    14.5000          14.2500         14.5000
19-Sep-96        9,600    14.7500          14.2500         14.5000
10-Jan-96       37,900    14.7500          14.5000         14.5000        9,170,300   0.41098
24-Oct-96      160,600    15.5000          14.5000         14.7500
23-Oct-96       96,100    15.5000          14.2500         14.7500
07-Oct-96       61,700    14.7500          14.2500         14.7500
09-Aug-96       13,300    15.5000          14.3750         14.7500
06-Aug-96       17,800    15.5000          14.7500         14.7500
08-Jul-96       36,800    14.7500          14.2500         14.7500
05-Jul-96       73,800    15.2500          14.5000         14.7500
03-Jul-96       78,600    15.6250          14.6250         14.7500
09-Jan-96       74,400    14.7500          14.0000         14.7500
05-Jan-96       66,600    15.5000          14.7500         14.7500
07-Aug-96       21,500    15.0000          14.7500         14.8750
25-Jul-96       28,200    15.2500          14.7500         14.8750
09-Jul-96       16,900    15.0000          14.6250         14.8750
01-Jul-96       12,900    15.2500          14.8750         14.8750
02-Oct-96       21,700    15.0000          14.2500         15.0000
01-Oct-96       34,100    15.0000          14.2500         15.0000
26-Sep-96      233,600    15.0000          14.2500         15.0000
11-Sep-96       24,600    15.8750          15.0000         15.0000
08-Aug-96       29,400    15.0000          14.2500         15.0000
23-Jul-96       50,000    15.5000          15.0000         15.0000
17-Jul-96       29,800    15.8750          15.0000         15.0000
16-Jul-96       51,400    15.0000          14.0000         15.0000
02-Jul-96       14,800    15.5000          15.0000         15.0000
28-Jun-96       26,100    15.6250          14.8750         15.0000
22-Dec-95      126,600    15.0000          13.8750         15.0000
29-Jul-96       15,600    15.2500          15.0000         15.1250
24-Jul-96       60,600    15.1250          14.7500         15.1250
27-Jun-96       11,200    15.5000          15.0000         15.1250
26-Jun-96        6,000    17.0000          14.8750         15.1250
05-Aug-96       15,700    16.2500          15.2500         15.2500
26-Jul-96       38,300    15.2500          14.8750         15.2500
30-Jan-96       13,400    15.7500          15.2500         15.2500
31-Jul-96       24,200    16.0000          15.3750         15.3750
04-Jan-96       83,600    16.3750          15.0000         15.3750
26-Dec-95       88,500    15.7500          14.8750         15.3750
28-Oct-96       42,100    15.5000          15.0000         15.5000
25-Oct-96       73,800    15.5000          14.7500         15.5000
12-Aug-96          700    15.5000          14.7500         15.5000
22-Jul-96       29,500    15.5000          15.0000         15.5000
19-Jul-96       19,900    16.0000          15.2500         15.5000
18-Jul-96       11,200    15.7500          15.0000         15.5000
27-Dec-95       36,200    15.7500          15.2500         15.5000
30-Oct-96       38,300    15.7500          15.5000         15.6250
02-Aug-96       11,700    16.2500          15.6250         15.6250
29-Jan-96       20,000    16.2500          15.5000         15.6250
08-Nov-96        9,700    16.5000          15.7500         15.7500
05-Nov-96        6,600    16.0000          15.5000         15.7500
01-Nov-96       79,700    16.5000          15.5000         15.7500
29-Oct-96       51,500    16.0000          14.7500         15.7500
10-Sep-96        5,300    16.0000          15.5000         15.7500
29-Aug-96       43,200    16.6250          15.7500         15.7500
27-Aug-96       17,000    16.5000          15.5000         15.7500
26-Aug-96       21,400    16.5000          15.7500         15.7500
13-Aug-96       31,500    15.7500          14.7500         15.7500
30-Jul-96       62,100    15.7500          15.0000         15.7500
26-Jan-96       21,100    16.2500          15.7500         15.7500
23-Jan-96       16,800    16.0000          15.2500         15.7500
22-Jan-96       17,700    15.7500          15.5000         15.7500
19-Jan-96       36,300    15.7500          15.3750         15.7500
18-Jan-96       59,700    16.7500          15.2500         15.7500
03-Sep-96       15,900    16.0000          15.2500         15.8750
25-Jan-96       23,900    16.2500          15.2656         15.8750
15-Jan-96       38,200    16.1250          15.7500         15.8750
30-Aug-96       19,400    16.1250          15.5000         15.9375
06-Nov-96       19,200    16.2500          15.5000         16.0000
04-Nov-96       10,200    16.0000          15.5000         16.0000
31-Oct-96       25,400    16.0000          15.5000         16.0000
09-Sep-96       28,500    16.2500          15.7500         16.0000
23-Aug-96       39,600    16.2500          16.0000         16.0000
22-Aug-96       16,400    16.5000          16.0000         16.0000
21-Aug-96       19,600    16.5000          16.0000         16.0000
01-Aug-96       41,200    16.0000          15.3750         16.0000
03-Apr-96       50,800    17.0000          16.0000         16.0000
06-Feb-96       42,700    16.5000          16.0000         16.0000
24-Jan-96       23,900    16.0000          15.2500         16.0000
12-Jan-96       23,300    16.2500          15.8750         16.0000
03-Jan-96       81,200    16.6250          16.0000         16.0000
10-Apr-96       82,500    16.5000          16.0000         16.1250
28-Mar-96      113,900    16.5000          16.0000         16.1250
11-Jan-96      110,400    16.2500          14.6250         16.1250
28-Dec-95      216,700    16.7500          15.2500         16.1250
22-Nov-96      287,300    16.7500          16.2500         16.2500
21-Nov-96       57,400    17.0000          16.2500         16.2500
07-Nov-96        5,600    16.5000          15.7500         16.2500
06-Sep-96       29,900    16.2500          16.1250         16.2500
05-Sep-96       17,600    16.7500          16.2500         16.2500
14-Aug-96      144,900    16.7500          15.5500         16.2500
09-Apr-96      126,000    17.0000          16.0000         16.2500
26-Mar-96       57,700    16.7500          16.2500         16.2500
20-Mar-96      335,400    19.0000          15.0000         16.2500
07-Feb-96      325,900    16.2500          15.7500         16.2500
02-Feb-96       42,800    16.5000          16.0000         16.2500
01-Feb-96       48,700    16.2500          15.5000         16.2500
31-Jan-96       35,400    16.2500          15.2500         16.2500
11-Nov-96       63,800    16.5000          15.7500         16.3750
25-Jun-96       60,200    17.5000          16.3750         16.3750
02-Jan-96      176,000    17.2500          16.2500         16.3750
20-Aug-96        5,400    16.5000          16.0000         16.4375
10-Feb-98       15,800    16.5000          16.0000         16.5000
09-Feb-98       45,800    16.7500          16.0000         16.5000
04-Feb-98      265,500    17.7500          15.8750         16.5000
19-Nov-96       62,800    17.0000          16.5000         16.5000
14-Nov-96       45,900    17.0000          16.5000         16.5000
13-Nov-96       50,000    17.0000          16.5000         16.5000
12-Nov-96       26,600    17.0000          16.0000         16.5000
04-Sep-96       43,500    16.7500          15.7500         16.5000
12-Apr-96        6,400    17.0000          16.5000         16.5000
27-Mar-96      212,500    16.7500          16.2500         16.5000
21-Mar-96      165,400    16.5000          16.0000         16.5000
05-Feb-96       57,800    16.8750          16.0000         16.5000
28-Aug-96       32,500    16.7500          16.0000         16.5625
06-Feb-98       31,600    17.0000          16.6250         16.6250
02-Apr-96       23,000    17.0000          16.5000         16.6250
17-Jan-96       84,500    16.6250          16.0000         16.6250
16-Jan-96      101,700    17.0000          16.2500         16.6250
02-Dec-96       25,900    17.1250          16.7500         16.7500
29-Nov-96       19,100    17.1250          16.7500         16.7500
27-Nov-96       17,100    17.1250          16.5000         16.7500
26-Nov-96       13,700    17.0000          16.2500         16.7500
25-Nov-96       77,700    16.7500          16.2500         16.7500
20-Nov-96       25,600    17.0000          16.5000         16.7500
18-Nov-96       68,400    17.0000          16.5000         16.7500
19-Aug-96       52,800    17.3750          16.5000         16.7500
03-May-96       51,100    17.0000          16.2500         16.7500
02-May-96       37,000    16.7500          16.0000         16.7500
01-May-96      111,900    17.5000          16.2500         16.7500
11-Apr-96       54,700    16.7500          16.1250         16.7500
08-Feb-96       56,100    16.7500          15.8750         16.7500
05-Feb-98      110,800    17.0000          16.5000         16.8750
15-Apr-96       14,300    17.0000          16.5000         16.8750
27-Feb-98       94,800    17.3750          16.6250         17.0000
03-Dec-96       39,100    17.1250          16.7500         17.0000
15-Nov-96      168,700    17.0000          16.5000         17.0000
16-Aug-96      176,100    17.5000          16.7500         17.0000
17-Apr-96       21,900    17.3750          16.5000         17.0000
16-Apr-96       38,600    17.1250          16.5000         17.0000
08-Apr-96       87,300    17.5000          16.2500         17.0000
04-Apr-96      126,100    17.5000          16.6250         17.0000
25-Mar-96      147,000    17.5000          16.8750         17.0000
29-Dec-95      108,400    17.2500          16.1250         17.0000
02-Mar-98       46,800    17.2500          16.6250         17.1250
24-Jun-96      197,800    18.0000          17.1250         17.1250
19-Jun-96       46,200    17.2500          16.7500         17.1250
01-Apr-96       29,000    17.3750          17.0000         17.1875
26-Feb-98       73,900    17.8125          16.7500         17.2500
20-Jun-96       41,700    17.2500          17.0000         17.2500
18-Jun-96       32,800    17.5000          16.7500         17.2500
06-May-96       56,700    17.2500          16.5000         17.2500
30-Apr-96      138,900    18.0000          17.2500         17.2500
25-Apr-96       58,800    17.7500          17.2500         17.2500
29-Mar-96       67,100    17.2500          16.0000         17.2500
22-Mar-96      124,100    17.5000          16.5000         17.2500
15-Aug-96       72,900    17.3750          16.2500         17.3750
21-Jun-96       73,200    17.5000          16.7500         17.3750
07-Apr-98       67,200    18.1250          17.2500         17.5000
21-Apr-97        9,400    18.3750          17.5000         17.5000
17-Jun-96       42,800    18.0000          17.2500         17.5000
16-May-96      170,500    18.0000          17.2500         17.5000
15-May-96      176,900    18.5000          17.5000         17.5000
29-Apr-96      143,600    18.0000          17.5000         17.5000
26-Apr-96       53,500    17.7500          17.2500         17.5000
24-Apr-96       40,600    18.0000          17.2500         17.5000
19-Apr-96       35,800    17.8750          17.5000         17.5000
09-Feb-96      143,100    17.5000          16.0000         17.5000        1,078,2500  0.562814
08-Apr-98       32,900    18.0000          17.2500         17.6250
06-Jun-96       41,900    18.0000          17.6250         17.6250
29-May-96       37,300    18.0000          17.6250         17.6250
18-Apr-96      130,600    18.2500          17.2500         17.6875
24-Apr-97       61,100    18.2500          17.5000         17.7500
04-Dec-96       49,200    17.5000          16.8750         17.7500
14-Jun-96       18,400    18.1250          17.7500         17.7500
13-Jun-96        8,800    18.1250          17.7500         17.7500
12-Jun-96       45,100    18.5000          17.7500         17.7500
10-Jun-96       27,300    18.0000          17.7500         17.7500
07-Jun-96       45,700    18.0000          17.6250         17.7500
05-Jun-96       30,700    18.2500          17.6250         17.7500
28-May-96       22,900    18.2500          17.7500         17.7500
08-May-96       40,000    18.0000          17.7500         17.7500
07-May-96       90,700    18.2500          17.2500         17.7500
23-Apr-96      177,100    18.1250          17.7500         17.7500
22-Apr-96       66,400    18.0000          17.5000         17.7500
08-Mar-96       98,600    19.0000          17.5000         17.7500
13-Feb-96       75,600    18.2500          17.5000         17.7500
25-Feb-98       95,100    18.3750          17.5000         17.8125
24-May-96       34,900    18.2500          17.8750         17.8750
23-May-96      292,200    18.2500          17.8750         17.8750
22-May-96       25,800    18.2500          17.7500         17.8750
09-May-96       25,000    18.0000          17.7500         17.8750
12-Feb-96      143,300    18.2500          16.7500         17.8750
14-Apr-98      224,100    18.5000          17.5000         18.0000
09-Mar-98       58,900    18.7500          18.0000         18.0000
28-Apr-97       17,600    18.7500          18.0000         18.0000
22-Apr-97       30,100    18.3750          17.5000         18.0000
18-Apr-97      152,900    18.3750          17.7500         18.0000
11-Jun-96       26,200    18.0000          17.7500         18.0000
30-May-96       30,900    18.0000          17.6250         18.0000
21-May-96      146,400    18.0000          17.7500         18.0000
20-May-96       13,600    18.0000          17.6250         18.0000
17-May-96       37,000    18.0000          17.5000         18.0000
10-May-96       82,400    18.5000          17.8750         18.0000
11-Mar-96      184,800    18.0000          16.5000         18.0000
13-Apr-98       32,300    18.2500          17.8750         18.1250
06-Apr-98       36,900    18.2500          18.0000         18.1250
30-Apr-97       15,500    18.3750          17.8750         18.1250
16-Apr-97       47,500    18.2500          17.5000         18.1250
11-Apr-97       33,600    18.5000          17.5000         18.1250
04-Jun-96       11,800    18.2500          17.7500         18.1250
13-May-96      254,100    18.2500          17.8750         18.1250
31-Mar-98       64,300    18.5000          18.0000         18.1875
11-Mar-98       33,600    19.0000          18.1875         18.1875
24-Feb-98      122,600    19.3750          17.6250         18.1875
01-Apr-98       70,100    18.5000          18.0000         18.2188
09-Apr-98       51,200    18.5000          17.6250         18.2500
03-Apr-98       65,100    18.3750          18.0625         18.2500
30-Mar-98       52,600    18.7500          18.0625         18.2500
27-Mar-98      136,100    19.1875          18.0000         18.2500
29-Apr-98       48,800    18.7500          17.7500         18.2500
23-Apr-97        3,400    18.3750          18.0000         18.2500
17-Apr-97       15,300    18.3750          17.5000         18.2500
15-Apr-97       57,400    18.7500          17.6250         18.2500
03-Jun-96       28,200    18.5000          17.7500         18.2500
31-May-96       26,600    18.2500          17.6250         18.2500
12-Mar-98       13,500    18.5000          18.2500         18.3125
02-Apr-98       30,700    18.3750          18.0625         18.3750
12-Jan-98       22,300    19.0000          18.3750         18.3750
29-Dec-97       17,300    18.7500          18.1250         18.3750
16-Mar-98       13,100    18.7500          18.0000         18.5000
13-Mar-98       13,300    18.5000          18.0000         18.5000
26-Dec-97        5,600    19.2500          18.5000         18.5000
04-Mar-98       60,600    19.1250          18.1250         18.6250
12-Feb-98      133,800    20.9375          18.1250         18.6250
22-Dec-97       12,700    19.5000          18.6250         18.6250
14-May-96      123,600    18.7500          18.1250         18.6250
20-Feb-96       88,900    19.2500          18.2500         18.6250
18-Mar-98       28,900    19.0000          18.5000         18.7500
10-Mar-98       39,400    19.0000          18.0000         18.7500
06-Mar-98       60,500    19.2500          18.5000         18.7500
27-Jan-98        3,200    19.1250          18.7500         18.7500
15-Jan-98       33,100    19.0625          18.7500         18.7500
31-Dec-97       14,700    19.3750          18.5000         18.7500
24-Dec-97        6,000    18.8750          18.6250         18.7500
01-May-97       25,900    18.7500          18.0000         18.7500
25-Apr-97        9,400    18.7500          18.0000         18.7500
14-Apr-97       54,600    19.0000          18.2500         18.7500
09-Apr-97      434,600    19.1250          17.7500         18.7500
13-Mar-96       56,700    18.7500          18.2500         18.7500
12-Mar-96       99,700    18.7500          17.6250         18.7500
26-Feb-96       16,700    19.2500          18.5000         18.7500
19-Mar-98       11,600    19.0000          18.6250         18.7813
20-Apr-98       17,000    19.3750          18.7500         18.8750
05-Mar-98       70,000    19.0000          18.5000         18.8750
03-Mar-98      227,400    19.1250          17.0625         18.8750
23-Jan-98       39,200    19.5000          18.6250         18.8750
14-Jan-98       14,200    20.0000          18.8750         18.8750
30-Dec-97       37,600    19.2500          18.3750         18.8750
10-Apr-97      178,600    18.8750          18.0000         18.8750
05-Dec-96      169,200    19.2500          17.5000         18.8750
05-Mar-96      122,300    19.2500          18.7500         18.8750
21-Feb-96       70,000    19.0000          18.2500         18.8750
14-Feb-96      147,800    19.2500          17.7500         18.8750
23-Dec-97        6,800    19.5000          18.6250         18.9375
03-Apr-97      115,400    21.5000          18.2500         18.9375
17-Apr-98       10,200    19.4375          19.0000         19.0000
15-Apr-98       93,900    19.0000          17.5000         19.0000
17-Mar-98       67,800    19.0000          18.2500         19.0000
22-Jan-98       16,800    19.5000          18.8750         19.0000
06-Dec-96       72,900    19.0000          17.7500         19.0000
07-Mar-96       19,000    19.2500          18.7500         19.0000
06-Mar-96       29,800    19.2500          18.7500         19.0000
04-Mar-96       73,500    20.0000          19.0000         19.0000
27-Feb-96       22,600    19.5000          18.7500         19.0000
26-Jan-98       15,700    19.5000          18.5000         19.1250
09-Jan-98       47,600    19.5000          19.0000         19.1250
02-Jan-98       10,800    19.1250          18.5000         19.1250
19-Dec-97        9,000    19.5000          19.0000         19.1250
18-Dec-97       42,300    20.0000          19.1250         19.1250
27-Jun-97       21,700    19.9375          18.8750         19.1250
08-Apr-97       62,500    19.7500          18.5000         19.1250
15-Mar-96       54,700    19.3750          18.5000         19.1250
28-Feb-96       58,300    19.3750          18.7500         19.1250
16-Apr-98       59,200    19.7500          18.8750         19.2500
23-Feb-98      142,400    20.5000          18.5000         19.2500
21-Jan-98       71,700    20.2500          18.7500         19.2500
08-Jan-98       18,600    19.7500          18.8750         19.2500
04-Apr-97      157,900    19.7500          18.0000         19.2500
19-Mar-96       22,900    19.5000          18.7500         19.2500
14-Mar-96       29,100    19.2500          18.5000         19.2500
01-Mar-96      141,100    19.5000          18.7500         19.2500
23-Feb-96       92,300    19.5000          18.5000         19.2500
16-Feb-96       57,800    19.2500          18.7500         19.2500
15-Feb-96       75,500    19.2500          18.7500         19.2500
10-Dec-97       46,100    19.5000          19.2500         19.3750
08-Dec-97       25,300    20.0000          19.3750         19.3750
07-Apr-97      135,100    19.7500          19.0000         19.3750
03-Dec-97        4,900    19.6250          19.2500         19.4375
22-Feb-96       62,000    19.4375          18.5000         19.4375
21-Apr-98       38,900    19.6250          18.7500         19.5000
26-Mar-98       24,100    19.7500          19.2500         19.5000
11-Feb-98      113,400    19.9375          16.0000         19.5000
17-Dec-97       16,900    20.0000          19.2500         19.5000
04-Dec-97       36,500    19.8750          19.1250         19.5000
02-Dec-97       25,800    19.7500          19.5000         19.5000
28-Nov-97        3,600    19.7500          19.5000         19.5000
26-Nov-97       38,600    20.0000          19.5000         19.5000
19-Nov-97       13,000    20.1250          19.5000         19.5000
26-Jun-97       42,100    20.2500          19.5000         19.5000
18-Mar-96      247,400    19.5000          18.7500         19.5000
29-Feb-96       45,300    19.5000          19.0000         19.5000
27-Apr-98       32,700    19.7500          19.0000         19.5625
20-Nov-97       19,900    19.8750          19.5625         19.5625
25-Mar-98       25,800    20.0000          19.2500         19.6250
15-Dec-97       28,000    19.7500          19.2500         19.6250
11-Dec-97       23,400    19.7500          19.2500         19.6250
01-Dec-97       19,200    19.8750          19.5000         19.6250
24-Nov-97       38,700    20.0000          19.3750         19.6250
30-Jun-9        35,000    19.6250          18.7500         19.6250
24-Mar-9        43,200    20.2500          19.5000         19.6875
09-Dec-9        17,500    19.7500          19.3750         19.6875
29-Apr-9        27,700    20.3750          19.7500         19.7500
23-Mar-9        93,400    21.0000          19.2500         19.7500
03-Feb-98       26,800    20.8750          19.3125         19.7500
13-Jan-98       71,600    20.0000          18.1250         19.7500
16-Dec-97       11,800    20.0000          19.7500         19.7500
12-Dec-97       19,100    19.7500          19.2500         19.7500
13-Nov-97       19,000    20.0000          19.5000         19.7500
25-Jun-97       11,000    20.0000          19.7500         19.7500
09-Dec-96       90,700    20.0000          18.7500         19.7500
28-Apr-98       42,600    20.2500          19.3750         19.8750
05-Dec-97       35,300    19.8750          19.0000         19.8750
21-Nov-97        7,000    19.8750          19.5000         19.8750
18-Nov-97       17,500    20.1250          19.5000         19.8750
14-Nov-97        4,100    20.3750          19.6250         19.9375
24-Apr-98       36,200    20.5000          19.8750         20.0000
23-Apr-98       45,800    20.7500          19.8750         20.0000
20-Feb-98      100,400    21.2500          20.0000         20.0000
25-Nov-97       13,500    20.0000          19.5000         20.0000
17-Nov-97       10,400    20.5000          19.6250         20.0000
24-Jun-97       16,500    20.5000          19.8125         20.0000
23-Jun-97       16,900    20.5000          20.0000         20.0000
20-Jun-97       58,100    20.8125          20.0000         20.0000
22-Apr-98       86,400    20.3750          19.8750         20.1250
27-Oct-97       34,700    20.7500          20.1250         20.1250
20-Mar-98      122,800    20.6250          18.6250         20.2500
20-Jan-98       32,400    21.8750          19.7500         20.2500
12-Nov-97       13,700    20.3750          20.0000         20.2500
23-Oct-97       59,100    21.0000          19.7500         20.2500
01-Jul-97       20,800    20.2500          19.5000         20.2500
29-Jan-98       21,600    21.1250          19.7500         20.3750
18-Jun-97       28,880    21.1250          20.2500         20.3750
11-Nov-97       15,000    21.0000          20.2500         20.4375
30-Apr-98       73,300    20.5000          19.7500         20.5000
28-Jan-98       51,800    21.3750          19.1250         20.5000
07-Jan-98       12,700    21.0000          19.8750         20.5000
05-Nov-97       16,200    20.8750          20.1250         20.5000       10,739,100   0.714036
13-Feb-98      409,900    21.5000          20.0000         20.6250
30-Jan-98        9,100    20.8750          19.7500         20.6250
02-Feb-98       31,700    21.5000          20.1250         20.7500
05-Jan-98       42,700    20.7500          18.7500         20.7500
07-Nov-97       17,800    20.7500          20.0000         20.7500
30-Oct-97        5,100    21.0000          20.5000         20.7500
28-Oct-97       50,800    21.0000          19.5000         20.7500
24-Oct-97      244,000    20.7500          20.0000         20.7500
19-Jun-97       23,400    20.7500          20.2500         20.7500
10-Nov-97       25,400    21.0000          20.2500         20.8750
06-Nov-97       11,600    20.8750          20.0000         20.8750
04-Nov-97       41,900    23.1250          20.8750         20.8750
17-Jun-98      316,800    24.1250          21.0000         21.0000
19-Feb-98      108,500    22.0000          21.6250         21.0000
06-Jan-98       13,500    21.0000          20.2500         21.0000
29-Oct-97       60,500    21.2500          20.5000         21.0000
02-May-97       93,700    21.1250          19.1250         21.1250
31-Oct-97        6,900    21.5000          21.0000         21.2500
17-Jun-97       53,100    22.5000          21.0000         21.2500
21-May-97        3,500    21.7500          21.2500         21.2500
17-Dec-96       69,700    22.5000          21.0000         21.2500
07-May-97       36,700    22.0000          21.2500         21.3750
18-Feb-98       91,200    22.5000          21.5000         21.5000
22-Jul-97       77,500    22.1250          21.5000         21.5000
13-May-97       31,800    22.2500          21.5000         21.5000
08-May-97      107,700    22.0000          21.5000         21.5000
31-Dec-96       32,900    21.6250          21.0000         21.5000
20-Dec-96       30,300    22.2500          21.5000         21.5000
18-Dec-96      302,800    22.0000          20.0000         21.5000
14-May-97        8,100    21.7500          21.3750         21.5625
24-Dec-96       19,200    21.7500          21.5000         21.5625
02-Jul-97       54,800    21.7500          20.5000         21.6250
23-Dec-96       27,900    21.7500          21.5000         21.6250
20-May-97       19,200    22.1250          21.5000         21.6875
16-Jan-98       44,900    21.7500          18.7500         21.7500
22-Oct-97       38,000    22.7500          21.7500         21.7500
19-May-97       12,700    22.1250          21.7500         21.7500
02-Apr-97       36,100    23.0000          21.5000         21.7500
08-Jan-97       69,900    22.7500          21.0000         21.7500
02-Jan-97       50,200    22.0000          21.0000         21.7500
30-Dec-96       38,400    21.7500          21.5000         21.7500
27-Dec-96       21,000    21.7500          21.5000         21.7500
26-Dec-96       10,400    21.7500          21.5000         21.7500
23-Jul-97      321,200    22.2500          21.2500         21.9375
04-Aug-97        7,800    22.2500          22.0000         22.0000
03-Jul-97       22,700    22.0000          21.5000         22.0000
22-May-97       48,300    22.2500          20.8750         22.0000
16-May-97       27,800    22.3750          21.6250         22.0000
12-May-97       13,500    22.2500          21.8750         22.0000
09-May-97      129,300    22.2500          22.0000         22.0000
19-Dec-96      163,900    23.2500          21.5000         22.0000
01-Aug-97       50,200    22.5000          22.0000         22.1250
15-May-97       41,100    22.2500          21.2500         22.1250
06-May-97       84,300    23.1250          21.7500         22.1250
05-May-98      143,800    22.6250          22.1875         22.2500
21-Jul-97       30,100    23.0000          22.0000         22.2500
23-May-97       36,900    22.6250          21.7500         22.2500
09-Jan-97       49,800    22.7500          21.2500         22.2500
10-Dec-96      657,900    23.3750          19.2500         22.2500
31-Jul-97       82,200    22.7500          22.2500         22.4375
17-Feb-98      255,500    22.5000          20.3750         22.5000
30-Jul-97       18,600    22.7500          22.4375         22.5000
24-Jul-97       41,200    22.6250          21.7500         22.5000
07-Jan-97       40,900    23.2500          22.2500         22.5000
16-Dec-96      400,700    24.7500          22.2500         22.5000
29-Jul-97       22,100    22.7500          22.2500         22.5625
28-Jul-97       63,500    23.2500          22.2500         22.5625
04-May-98      387,300    23.1250          22.6250         22.6250
03-Nov-97       26,100    22.8750          21.0000         22.6250
06-Aug-97       13,900    22.7500          22.2500         22.6250
05-Aug-97       13,500    22.6250          22.0000         22.6250
25-Jul-97       53,900    23.1250          22.1250         22.6250
05-Jun-97       60,100    22.8750          22.2500         22.6250
12-Jun-98      206,800    23.8750          22.7500         22.7500
07-Jul-97       60,500    23.3750          21.5000         22.7500
16-Jun-97       33,700    23.0000          22.5000         22.7500
13-Jun-97       31,400    23.2500          22.5000         22.7500
06-Jun-97       32,600    22.8125          22.6250         22.7500
05-May-97      163,000    24.1250          21.0000         22.7500
12-Aug-97      152,000    23.6250          22.6250         22.7813
01-May-98      532,500    23.2500          21.5000         22.8125
09-Jun-97      159,700    23.1250          22.7500         22.8125
10-Jun-97      182,900    23.2500          22.7500         22.8750
27-May-97       35,700    23.0000          21.8750         22.8750
12-Dec-96      175,900    23.5000          22.0000         22.8750
17-Oct-97       10,800    23.5000          22.7500         22.9375
29-Jun-98       48,400    23.5000          23.0000         23.0000
06-May-98      307,000    25.2500          22.1875         23.0000
21-Oct-97       20,000    23.0000          22.7500         23.0000
20-Oct-97       30,900    23.5000          22.8750         23.0000
24-Sep-97        9,000    23.5000          22.7500         23.0000
18-Jul-97       31,300    23.6250          22.5000         23.0000
12-Jun-97       24,300    23.5000          23.0000         23.0000
28-May-97      194,600    23.2500          22.6250         23.0000
13-Jan-97      100,500    24.5000          22.8750         23.0000
06-Jan-97       63,900    24.0000          22.2500         23.0000
11-Dec-96      405,800    24.2500          21.2500         23.0000
23-Sep-97       40,900    23.2500          22.7500         23.0625
15-Jun-98      110,100    23.5000          22.6250         23.1250
02-Jun-98       43,400    23.5625          23.0000         23.1250
16-Oct-97       48,600    23.3750          23.1250         23.1250
10-Oct-97        8,500    23.7500          23.0000         23.1250
09-Oct-97        5,000    23.2500          23.1250         23.1250
11-Jun-97      185,500    23.2500          22.7500         23.1250
07-May-98       88,700    23.2500          22.5000         23.1875
01-Oct-97       29,700    23.6250          23.1250         23.1875
19-Sep-97       34,200    23.8125          22.8750         23.1875
26-Jun-98       65,300    24.0000          22.8750         23.2500
18-Jun-98      127,100    23.3750          21.8750         23.2500
15-Oct-97       17,900    23.2500          23.0000         23.2500
08-Oct-97        7,400    24.0000          23.2500         23.2500
03-Oct-97       11,100    23.6250          23.2500         23.2500
13-Aug-97       55,400    23.6250          23.0000         23.2500
15-Jul-97       66,900    23.5000          23.0000         23.2500
10-Jul-97       67,600    23.5000          23.2500         23.2500
04-Jun-97       67,100    25.0000          23.2500         23.2500
31-Mar-97       43,000    24.7500          23.2500         23.2500
14-Jan-97       61,400    23.6250          22.7500         23.2500
22-Jun-98      131,900    24.0000          23.2500         23.3750
01-Jun-98       24,500    23.7500          23.0000         23.3750
14-Oct-97       21,600    23.3750          23.1250         23.3750
29-Sep-97       19,700    24.3750          23.0000         23.3750
11-Jul-97      190,200    23.7500          23.2500         23.3750
28-May-98       55,700    23.6250          22.8750         23.4375
09-Jul-98       67,100    23.8750          23.2500         23.5000
03-Jun-98       26,300    23.5000          23.1250         23.5000
30-Sep-97        9,500    23.5000          22.8750         23.5000
25-Sep-97       10,100    23.5000          23.0000         23.5000
22-Aug-97       79,500    23.9375          23.1250         23.5000
14-Jul-97      136,200    23.7500          23.2500         23.5000
30-May-97       13,800    23.5000          23.0000         23.5000
29-May-97       19,700    23.5000          22.7500         23.5000
01-Apr-97        6,500    23.5000          23.0000         23.5000       11,119,700                      0.870618
19-Jun-98       59,400    23.7500          22.9375         23.5625
08-May-98       52,300    23.6250          22.7500         23.5625
07-Oct-97        9,500    24.0000          23.3750         23.5625
17-Jul-97       52,300    23.7500          23.1250         23.5625
02-Jun-97       22,700    23.6250          23.0000         23.5938
08-Jul-98      111,500    24.0000          23.0000         23.6250
29-May-98       39,800    23.6250          23.2500         23.6250
15-May-98       53,400    23.8750          23.5000         23.6250
13-Oct-97        9,700    23.6250          23.1250         23.6250
02-Oct-97        1,300    23.6250          23.1250         23.6250
22-Sep-97        6,200    23.6250          23.0000         23.6250
11-Aug-97      167,200    24.8750          23.3750         23.6250
13-Jul-98       11,200    24.2500          23.5000         23.6875
23-Jun-98      105,800    23.6875          23.0000         23.6875
27-May-98       19,300    23.7500          23.0000         23.6875
20-May-98       16,300    24.0000          23.5625         23.6875
25-Jun-98      145,200    25.0000          23.7500         23.7500
26-May-98       70,900    24.6250          23.7500         23.7500
06-Oct-97        8,600    23.8750          23.1250         23.7500
15-Sep-97       11,000    23.8125          23.7500         23.7500
21-Aug-97       51,200    24.0000          23.7500         23.7500
09-Jul-97       56,700    24.0000          23.2500         23.7500
10-Jan-97      251,400    24.5000          21.5000         23.7500
18-May-98       70,600    23.8750          23.5000         23.7813
14-May-98      105,800    24.2500          23.5000         23.8125
19-May-98       14,400    23.8750          23.6250         23.8438
07-Jul-98      146,300    24.0000          23.7500         23.8750
02-Jul-98      152,200    24.3750          23.7500         23.8750
11-Sep-97       21,500    24.1250          23.8750         23.8750
16-Jul-97      224,100    23.8750          22.6875         23.8750
24-Jun-98      118,400    24.0000          23.2500         23.9375
10-Jun-98       26,700    24.5000          23.6250         23.9375
18-Sep-97      153,300    25.0000          23.3750         23.9375
12-Sep-97        6,900    24.1250          23.7500         23.9375
06-Jul-98       67,300    24.1250          23.5000         24.0000
01-Jul-98       64,300    24.3125          23.8750         24.0000
11-Jun-98       11,900    24.1250          23.7500         24.0000
11-May-98      181,000    24.5000          23.0000         24.0000
10-Sep-97       13,300    24.7500          24.0000         24.0000
27-Aug-97       15,500    24.5000          24.0000         24.0000
20-Aug-97       38,400    24.2500          23.8750         24.0000
19-Aug-97       34,200    24.5000          23.7500         24.0000
15-Aug-97       22,700    24.2500          23.6250         24.0000
08-Jul-97      181,500    24.0000          20.8750         24.0000
29-Jan-97       30,800    24.7500          24.0000         24.0000
28-Jan-97       44,100    24.5000          23.7500         24.0000
27-Jan-97      151,000    25.0000          23.7500         24.0000
03-Jan-97      172,900    24.2500          21.5000         24.0000
13-Dec-96      288,900    25.2500          22.0000         24.0000
30-Jun-98      158,300    24.5000          23.1250         24.0313
16-Jun-98       35,400    24.2500          23.1250         24.0625
21-May-98       45,100    24.2500          23.5000         24.0625
10-Jul-98       50,700    24.2500          23.5000         24.1250
13-May-98      122,000    24.5000          23.6250         24.1250
12-May-98      129,400    24.2500          23.6875         24.1250
26-Sep-97       24,900    24.1250          23.0000         24.1250
14-Jul-98       65,600    24.3750          23.6875         24.1875
15-Jul-98       26,500    24.5000          24.2500         24.2500
08-Jun-98       17,500    24.4375          24.0000         24.2500
22-May-98       53,800    24.2500          23.8125         24.2500
26-Aug-97       29,800    24.5000          24.0000         24.2500
25-Aug-97       60,400    24.5000          23.3750         24.2500
18-Aug-97       40,600    24.2500          23.7500         24.2500
14-Aug-97       62,800    24.2500          23.1875         24.2500
09-Jun-98       62,700    24.3750          23.3750         24.3750
08-Sep-97       12,300    25.0000          24.3750         24.3750
28-Aug-97        9,800    24.5000          24.0000         24.3750
05-Sep-97        9,100    25.0000          24.5000         24.5000
04-Sep-97       10,900    25.0000          24.5000         24.5000
07-Aug-97      304,500    24.5000          22.3750         24.5000
03-Jun-97       64,600    25.0000          23.5625         24.5000
05-Jun-98       68,500    25.0000          24.2500         24.6250
08-Aug-97       85,100    25.0000          23.7500         24.6250
24-Jan-97       53,900    25.5000          24.6250         24.6250
16-Jul-98       70,000    25.0000          24.0000         24.7500
02-Sep-97       22,600    24.8750          24.0000         24.7500
29-Aug-97       27,500    24.7500          23.8750         24.7500
27-Mar-97       65,000    25.2500          24.0000         24.7500
24-Mar-97       52,700    25.7500          24.3750         24.7500
30-Jan-97      104,100    25.0000          23.7500         24.7500
23-Jan-97       34,100    25.7500          24.7500         24.7500
09-Sep-97       16,000    25.0000          24.3750         24.9844
04-Jun-98       63,100    25.0000          23.3750         25.0000
17-Sep-97       18,300    25.5000          24.7500         25.0000
16-Sep-97       93,200    25.3750          23.6250         25.0000
03-Sep-97       15,000    25.0000          24.3750         25.0000
25-Mar-97       27,500    25.1250          24.3750         25.0000
22-Jan-97      111,600    25.7500          24.7500         25.0000
15-Jan-97      173,900    25.5000          23.0000         25.2500
19-Feb-97       21,700    26.2500          25.5000         25.5000
11-Feb-97       35,000    26.2500          25.2500         25.5000
31-Jan-97      137,000    26.3750          24.2500         25.5000
21-Jan-97       42,800    26.2500          25.5000         25.5000
20-Jan-97       75,200    27.2500          25.1250         25.5000
26-Mar-97       34,400    25.6250          24.2500         25.6250
13-Feb-97       93,700    26.1250          25.2500         25.6250
21-Mar-97       37,600    26.7500          25.7500         25.7500
21-Feb-97       32,800    26.7500          25.7500         25.7500
18-Feb-97       12,500    26.0000          25.5000         26.0000
04-Feb-97       32,900    27.5000          26.0000         26.0000
03-Mar-97        7,200    26.1250          25.6250         26.0625
28-Feb-97       40,800    26.5000          25.7500         26.1250
26-Feb-97       27,500    26.6250          26.1250         26.1250
25-Feb-97       41,000    26.5000          26.1250         26.1250
24-Feb-97       39,000    26.6250          25.7500         26.1250
14-Feb-97       19,300    26.1250          25.5000         26.1250
12-Feb-97       32,600    26.1250          25.2500         26.1250
10-Feb-97       16,500    27.0000          26.0000         26.2500
04-Mar-97       42,400    27.0000          25.5000         26.3750
20-Mar-97       37,700    26.7500          26.2500         26.5000
05-Mar-97      120,200    28.0000          26.2500         26.5000
07-Feb-97      105,100    28.5000          26.3750         26.5000        7,274,600                      0.973055
20-Feb-97      111,900    27.0000          25.2500         26.6250
18-Mar-97       33,000    27.2500          26.7500         26.7500
06-Mar-97       88,500    28.0000          26.5000         26.7500
11-Mar-97       80,000    28.5000          26.7500         26.8750
19-Mar-97      110,300    27.0000          26.5000         27.0000
17-Mar-97       52,400    27.6250          26.7500         27.0000
13-Mar-97       21,500    27.5000          26.7500         27.0000
07-Mar-97       27,000    27.5000          26.7500         27.0000
27-Feb-97       36,700    27.0000          26.1250         27.0000
12-Mar-97       49,700    28.0000          26.7500         27.1250
14-Mar-97       57,700    28.1250          26.7500         27.2500
03-Feb-97      175,500    27.5000          24.7500         27.2500
17-Jan-97      251,600    29.2500          27.0000         27.7500
06-Feb-97       99,700    29.0000          27.8750         27.8750
10-Mar-97       76,900    28.5000          26.8750         28.0000
05-Feb-97      201,400    28.5000          26.2500         28.2500
16-Jan-97      439,700    29.2500          25.5000         29.1250        1,913,500                      1

            71,015,300










                                                       WASSERSTEIN PERELLA & CO.
- --------------------------------------------------------------------------------



MYCOGEN CORPORATION                       BACKGROUND OF THE PROPOSED TRANSACTION
- --------------------------------------------------------------------------------
TRANSACTION RATIONALE

- -  MARKET FORCES MAKE MYCOGEN STRATEGICALLY IMPORTANT TO DOW

   -  The intellectual property positions of agricultural biotechnology 
      businesses are well-established, possibly foreclosing the opportunity 
      for new entrants or greenfield initiatives

   -  Imminent success of first generation biotech products for corn and soy 
      will likely trigger high valuations, making future collaborations with 
      agrochemical companies far more expensive

   -  "Gene stacking" creates an urgency for agchem companies to find their 
      biotech partner quickly or risk being rendered obsolete by super seeds 
      that have performance characteristics that complement products of 
      competitors

   -  Dow has been slower than rivals Monsanto, DuPont and AgrEvo in 
      acquiring the technology it needs to compete in the promising market 
      for genetically engineered crops

   -  The heightened pace of alliances between agchem and biotech companies 
      (DuPont-Pioneer, American Home Products-Monsanto-Dekalb) makes it 
      imperative for Dow to strengthen its biotech capabilities

- -  MYCOGEN OFFERS DOW AN UNIQUE OPPORTUNITY

   -  Entry into the broader life science market

   -  High value-added biotech traits with freedom to operate

   -  Access to transformation technology

   -  Access to Ahlquist and Demeter technologies

   -  A credible seed platform

      -  Access to more than 20% of North American farm operations

      -  Modern production facilities with state of the art business systems

      -  Strong positions in Argentina and Brazil provide an opportunity to 
         bundle traits and more effectively compete with Monsanto




                                                       WASSERSTEIN PERELLA & CO.
- --------------------------------------------------------------------------------



MYCOGEN                                      BACKGROUND OF PROPOSED TRANSACTION
- -------------------------------------------------------------------------------
BAR CHART OF 1997 AGRICULTURAL CROP PROTECTION SALES OF LEADING COMPANIES 
  (IN $MM)



                   Growth       Op. Marg.     Total
                     %              %           $
                                     
Monsanto + AHP     [    ]       [    ]         5,245

Novartis            20.7         19.9          4,198 (A)

Monsanto            22.3         23.8          3,126 (B)

Zeneca              (3.1)        13.7          2,674 (C)

DUPONT               1.9         18.8          2,518 (D)

Hoechst             11.8          7.7          2,347 (E)
(AgrEvo)

Bayer               10.6         16.6          2,264

Rhone-Poulenc       12.0         13.5          2,200

American             6.6         20.3          2,119
Home Products

BASF(4)             42.9         14.6          1,875 (F)

Dow Agrosciences    11.0          NA           1,613 (G)

FMC                  1.5          6.2            628

Rohm & Haas         (2.3)         8.2            502



- ---------------

(A)  May-97   Merck - Crop Protection               Value    $910*

(B)  May-98   Dekalb Genetics (60%)                 Value  $2,400*
              Delta Pine and Land (95%)             Value  $1,850*
     Apr-98   GeneTrace plant genomics rights       Value   $17.2*
     Mar-98   Dekalb Genetics announces
              consideration of sale -- Monsanto,
              Novartis, and others considering bids            --
     Nov-97   Sementes Agroceres                               NA
     Apr-97   Calgene (Rest of Stake)               Value    $240*
     Feb-97   Asgrow Agronomics                     Value    $240*
     Jan-97   Holden's Foundation Seeds,            Value  $1,020*
              Corn States Hybrid Svc.,
              Corn States Int'l.
     Dec-96   Announces Chemical Spinoff                       NA
     Aug-96   Calgene (5.1% Stake)                  Value     $50*
     May-96   Agracetus Plant Sci.                  Value    $150*
     Apr-96   Calgene (49.9% Stake)                 Value    $258*(1)
     Mar-96   Dekalb Genetics (40% Stake)           Value    $152*
     Nov-95   Rights to Ecogen's gene technology    Value     $25*

(C)  Dec-97   Fungicide Business of ISK, Japan      Value    $500*
     Jun-97   Mogen International                   Value     $74*

(D)  Aug-97   Pioneer Hi-Bred Int'l (20% Stake)     Value  $1,700*
     Aug-97   Protein Tech Int'l (PDI)              Value  $1,500*
              (Ralston Purina Company)

(E)  Sep-97   Sunseed Company                                  --
     Sep-96   Plant Genetic Systems                 Value    $733*
     1996     PlantTec (20% initial investment)                --

(F)  Feb-98   Researach agreement with Fytochem                NA
     Jan-97   Sandoz Corn Herbicides                Value    $778*

(G)  Apr-98   Buyout proposal for Mycogen                      --
     Apr-98   Research deal with BTG                           NA
     Mar-98   Dow ups stake in
              Mycogen to 69%
     Feb-98   Cereal Derived Functional
              Ingredients                                      NA
     Jan-98   Raises Mycogen stake to
              63%, along with transfer
              of 16.3% of Vernevil                  Value     $94*
     Dec-97   SemBioSys investment                  Value     $17*
     Dec-97   Garst Seed Co licensing                          NA
     Dec-97   Sentrachem and Sanachem               Value    $487*(2)
     May-97   Dow Elanco (40% Stake)                Value    $900*
     Dec-96   Mycogen (additonal 4.5% Stake)        Value     $17*
     Jan-96   Mycogen (47% Stake)                   Value    $158*

* All Values in $MM

- -------------------------------
(1) Includes $30MM cash and Monsanto's 100% ownership of Gargiolo L.P.
(2) Does not include $300MM in undistributed earnings to be paid to Lilly 
    upon completion.
(3) Less certain undisclosed liabilities.
(4) BASF operating income excludes $46 million in integration and inventory 
    step-up costs.

                                                     WASSERSTEIN PERELLA & CO.
- ------------------------------------------------------------------------------



MYCOGEN                                 BACKGROUND OF THE PROPOSED TRANSACTION
- ------------------------------------------------------------------------------
DIAGRAM OF ALLIANCES AND TRANSACTIONS IN THE SEED INDUSTRY





- ------------------------------------------------------------------------------
                            ALLIANCE RATIONALE
- ------------------------------------------------------------------------------

 - Genetic engineering & traditional agricultural seeds = valued added 
                                                          benefits: herbicide 
                                                          tolerance, 
                                                          insecticide/fungal 
                                                          resistance, trait 
                                                          (oil or protein 
                                                          content) and yield 
                                                          improvement

 - Agchem companies need seed alliances for farmer relationships and 
   germplasm - the delivery vehicle for modified genes
   - Monsanto paid ~ 14x sales for Holden's foundation seeds following an 
     active auction
   - Dekalb Seeds was valued at over 8.2x LTM Sales following a strong cover 
     bid from Novartis.
 - Monsanto (Roundup-Ready) and AgrEvo (Liberty-Link) forecast gene modified 
ag products to account for ~ 1/3 their post 2000 sales.

- ------------------------------------------------------------------------------

                                                     WASSERSTEIN PERELLA & CO.
- ------------------------------------------------------------------------------



MYCOGEN CORPORATION                       BACKGROUND OF THE PROPOSED TRANSACTION
- --------------------------------------------------------------------------------
REVIEW OF PROCESS TO DATE

- - ON APRIL 30, 1998 DOW, THROUGH DOW AGROSCIENCES LLC ("DAS"), PROPOSED:

     -  To amend the Exchange and Purchase Agreement executed on January 15, 
        1996 by Mycogen, Agrigenetics, Inc., DowElanco and United Agriseed, Inc.

     -  To acquire for $20.50 per share all of the outstanding shares of 
        Mycogen not already owned by Dow and its affiliates

- -  ON APRIL 30, 1998, MYCOGEN'S BOARD OF DIRECTORS APPOINTED A SPECIAL 
   COMMITTEE OF INDEPENDENT DIRECTORS TO CONSIDER DOW'S PROPOSAL

- -  IN EARLY MAY, 1998, THE SPECIAL COMMITTEE RETAINED ALTHEIMER & GRAY AS 
   ITS LEGAL ADVISOR

- -  DURING THE FIRST TWO WEEKS OF MAY 1998, THE SPECIAL COMMITTEE INTERVIEWED 
   A NUMBER OF INVESTMENT BANKING FIRMS. ON MAY 26, 1998, THE COMPANY 
   ANNOUNCED THAT WASSERSTEIN PERELLA & CO., INC. ("WP&CO.") HAD BEEN RETAINED 
   AS FINANCIAL ADVISOR TO THE SPECIAL COMMITTEE

- -  ON MAY 27, 1998, MEMBERS OF WP&CO. AND ALTHEIMER & GRAY MET WITH MYCOGEN'S 
   SENIOR MANAGEMENT AT THE COMPANY'S HEADQUARTERS IN SAN DIEGO, CA TO DISCUSS 
   THE COMPANY'S OPERATIONS, BUSINESS STRATEGY, INTELLECTUAL PROPERTY PORTFOLIO,
   PATENT LITIGATION, DAS' INVESTMENT IN MYCOGEN AND OTHER DUE DILIGENCE ITEMS

- -  DURING THE WEEK OF JUNE 1, 1998, WP&CO. AND ALTHEIMER & GRAY CONDUCTED 
   ADDITIONAL DUE DILIGENCE AND REVIEWED VARIOUS BUSINESS, FINANCIAL AND LEGAL 
   MATERIALS PROVIDED BY THE COMPANY

- -  FROM JUNE 8 THROUGH JUNE 11, 1998, MEMBERS OF WP&CO. AND ALTHEIMER & GRAY 
   CONDUCTED DETAILED DUE DILIGENCE AT THE COMPANY'S SAN DIEGO HEADQUARTERS, 
   MEETING WITH MYCOGEN'S SENIOR MANAGEMENT, TECHNICAL AND INTELLECTUAL PROPERTY
   PERSONNEL, SENIOR MANAGEMENT OF THE COMPANY'S BUSINESS UNITS, AND 
   INTELLECTUAL PROPERTY COUNSEL

- -  ON JUNE 10, 1998, WP&CO. SENT A LETTER TO DOW REQUESTING A DUE DILIGENCE 
   MEETING WITH REPRESENTATIVES OF DOW AND DAS



                                                       WASSERSTEIN PERELLA & CO.
- --------------------------------------------------------------------------------




MYCOGEN CORPORATION                       BACKGROUND OF THE PROPOSED TRANSACTION
- --------------------------------------------------------------------------------
REVIEW OF PROCESS TO DATE (CONT'D)


- -  ON JUNE 11, 1998, THE HONORABLE CLAYTON YEUTTER WAS ELECTED TO MYCOGEN'S 
   BOARD OF DIRECTORS AND DESIGNATED TO REPLACE DR. GEORGE KHACHATOURIANS ON THE
   SPECIAL COMMITTEE. DR. KHACHATOURIANS, WHO HAD PERFORMED CERTAIN CONSULTING 
   SERVICES FOR DOW, VOLUNTARILY STEPPED DOWN FROM THE SPECIAL COMMITTEE TO 
   AVOID ANY APPEARANCE OF A POTENTIAL CONFLICT OF INTEREST

- -  IN ADDITION TO FACE-TO-FACE MEETINGS, WP&CO. AND ALTHEIMER & GRAY HAVE 
   CONDUCTED A NUMBER OF TELEPHONE CONVERSATIONS WITH THE COMPANY TO OBTAIN 
   ADDITIONAL DUE DILIGENCE MATERIALS

- -  ON JUNE 22, 1998 DOW RESPONDED TO WP&CO.'S JUNE 10TH LETTER AND AGREED TO 
   SCHEDULE A MEETING FOR JUNE 25, 1998 IN CHICAGO TO DISCUSS DUE DILIGENCE 
   ITEMS

- -  ON JUNE 25, 1998, THE SPECIAL COMMITTEE AND MEMBERS OF WP&CO. AND 
   ALTHEIMER & GRAY MET WITH REPRESENTATIVES OF DOW, DAS, SOLOMON SMITH BARNEY 
   AND MAYER, BROWN & PLATT TO GATHER ADDITIONAL INFORMATION REGARDING DOW'S 
   PROPOSAL



                                                       WASSERSTEIN PERELLA & CO.
- --------------------------------------------------------------------------------




MYCOGEN CORPORATION
- -------------------------------------------------------------------------------







                         ----------------------------------


                                 REVIEW OF MYCOGEN


                         ----------------------------------




                                                      WASSERSTEIN PERELLA & CO.
- -------------------------------------------------------------------------------


MYCOGEN CORPORATION                                          REVIEW OF MYCOGEN
- ------------------------------------------------------------------------------
OVERVIEW



                    
- ---------------------
BUSINESS DESCRIPTION    -   A DIVERSIFIED AGRIBUSINESS AND BIOTECHNOLOGY COMPANY
- ---------------------       THAT DEVELOPS AND MARKETS SEED FOR IMPROVED CROP 
                            VARIETIES AND PROVIDES CROP PROTECTION SERVICES

- ---------------------
BUSINESS SEGMENTS       -   SEED SEGMENT -- PRODUCES AND MARKETS SEED FOR 
- ---------------------       MAJOR AGRICULTURAL CROPS AND USES BIOTECHNOLOGY AND
                            TRADITIONAL AND MARKER-ASSISTED BREEDING TO DEVELOP
                            CROP VARIETIES WITH GENETICALLY ENHANCED PEST AND 
                            DISEASE RESISTANCE, IMPROVED VEGETABLE OIL PROFILES
                            AND OTHER VALUE-ADDED CHARACTERISTICS

                            -   Mycogen Seeds ranks fourth in the U.S. in sales
                                of seed corn, second in hybrid sunflower seed 
                                sales and is among the top five in soybean, 
                                sorghum and alfalfa sales

                            -   Morgan Seeds ranks second in Argentina in seed
                                corn sales and third in hybrid sunflower seed 
                                sales

                            -   Dinamilho holds 4% of the Brazil's overall corn
                                seed market, with a 10.2% share of Brazil's
                                high-tech corn seed market

                        -   CROP PROTECTION SEGMENT -- MANUFACTURES AND MARKETS
                            ENVIRONMENTALLY COMPATIBLE SPRAY-ON BIOPESTICIDE 
                            PRODUCTS. ALSO OPERATES SOILSERV, INC., WHICH 
                            PROVIDES CROP PROTECTION SERVICES TO GROWERS OF 
                            HIGH-VALUE CROPS

                            -   Biopesticide Products -- based on natural 
                                agents, such as proteins and fatty acid 
                                compounds, that have specific toxic activity
                                on target pests. The company's Bt-based 
                                biopesticides use the Company's proprietary
                                Cellcap technology

                            -   Soilserv -- monitors fields and uses customized
                                equipment to apply pest control products 
                                primarily in the Salinas Valley, CA and Yuma, AZ
                                regions

- ---------------------
ALLIANCES               -   VERNEUIL HOLDING, S.A. -- MYCOGEN HOLDS A 35% EQUITY
- ---------------------       STAKE IN VERNEUIL AND ENTERED AN AGREEMENT TO 
                            DEVELOP OILSEED PRODUCTS AND INSECT RESISTANT CORN

                        -   PIONEER HYBRID INTERNATIONAL -- 10-YEAR TECHNOLOGY
                            COLLABORATION TO DEVELOP INSECT RESISTANT TRAITS FOR
                            CORN, SOYBEAN, CANOLA, SUNFLOWER, SORGHUM AND WHEAT

                        -   J.G. BOSWELL -- JOINT VENTURE TO DEVELOP PEST AND 
                            HERBICIDE RESISTANT COTTON

- ---------------------
HEADQUARTERS            -   SAN DIEGO, CA
- ---------------------
- ---------------------
OWNERSHIP               -   DOW AGROSCIENCES, LLC -- 69%
- ---------------------




MYCOGEN CORPORATION                                          REVIEW OF MYCOGEN
- ------------------------------------------------------------------------------
MYCOGEN CORP. BEFORE ADJUSTMENTS - FINANCIAL SUMMARY ($MM)



- ------------------------------------------------------------------------------------------------------
                               1995        1996         1997         LTM         1998(1)      1999(1)
FY 8/31                      8/31/95     8/31/96      8/31/97      2/28/98       8/31/98      8/31/99
- ------------------------------------------------------------------------------------------------------
                                                                            
SALES                         $113.2     $155.6       $211.0       $214.0        $234.5       $247.5
Less: Cost of Sales             67.0       93.5        126.9        127.8            NA           NA
                                ----       ----        -----        -----          ----         ----
Gross Margin                    46.3       62.1         84.1         86.2            NA           NA
Less: S, G & A Expense          61.8      112.2        118.7        142.4            NA           NA
                                ----       ----        -----        -----          ----         ----
EBIT                           (15.5)     (50.1)       (34.5)       (56.2)        (12.5)         0.0
Less: Interest Exp.             (0.9)      (2.4)         1.6          2.9           1.5          1.5
Less: Other Exp. (Inc.)         (0.2)      (0.7)         0.0         (0.1)          0.0          0.0
                                ----       ----        -----        -----          ----         ----
EBT                            (14.4)     (47.1)       (36.1)       (59.0)        (14.0)        (1.5)
Less: Income Tax Exp.            0.0        0.0          1.5          0.6           0.0          0.0
Less: Pref. Div. & Min. Int.     1.5        0.6          0.0          0.0           0.0          0.0
                                ----       ----        -----        -----          ----         ----

NET INCOME                     (15.9)     (47.6)       (37.7)       (59.6)        (14.0)        (1.5)
- ------------------------------------------------------------------------------------------------------
EBIT                          ($15.5)    ($50.1)      ($34.5)      ($56.2)       ($12.5)        $0.0
Plus: Dep. & Amort.              9.0        9.1         10.0         11.6          12.7         13.4
                                ----       ----        -----        -----          ----         ----
EBITDA                          (6.5)     (41.1)       (24.5)       (44.6)          0.2         13.4
Less: Capital Exp.               6.6       13.9         35.7         36.0          39.5         41.7
                                ----       ----        -----        -----          ----         ----
FREE CASH FLOW                 (13.1)     (55.0)       (60.2)       (80.7)        (39.3)       (28.3)
- ------------------------------------------------------------------------------------------------------

- ------------------------------------------------------------------------------------------------------
                                         MARGINS
- ------------------------------------------------------------------------------------------------------
GROSS MARGIN                    40.9%      39.9%        39.9%        40.3%           NA           NA
EBITDA                          -5.8%     -26.4%       -11.6%       -20.9%          0.1%         5.4%
EBIT                           -13.7%     -32.2%       -16.4%       -26.3%         -5.3%         0.0%
NET INCOME                     -14.1%     -30.6%       -17.9%       -27.9%         -6.0%        -0.6%
FREE CASH FLOW                 -11.6%     -35.3%       -28.5%       -37.7%        -16.7%       -11.4%
- ------------------------------------------------------------------------------------------------------

- ------------------------------------------------------------------------------------------------------
                                          RATIOS
- ------------------------------------------------------------------------------------------------------
Book Value                        -      $181.2       $157.2       $210.2        $199.7       $198.2
RET. ON BOOK EQUITY (ROE)         -       -26.3%       -24.0%       -28.4%         -7.0%        -0.8%
Total Book Assets                 -       227.5        239.7        292.8            NA           NA
RET. ON BOOK ASSETS (ROA)         -       -21.6%       -15.3%       -19.8%           NA           NA
- ------------------------------------------------------------------------------------------------------

- ------------------------
FOOTNOTES
- ------------------------
(1) Next fiscal year results are based upon Furman Selz research report as of 
    3/13/98
(2) Book value of debt assumed to approximate market value

- -------------------------------------------------------------------------------
                           MARKET CAPITALIZATION
- -------------------------------------------------------------------------------


                                                          
STOCK PRICE (6/22/98)                                         $ 23.38
  52-WEEK HIGH/LOW:  $25.50/$15.88
Shares Outstanding - MYCO                                       36.11
                                                                -----
PRE-DILUTED EQUITY MARKET VALUE                                $844.1
- -------------------------------------------------------------------------------

Pre-Diluted Equity Market Value                                $844.1
Options Outstanding                                4.4
Average Strike Price                            $12.03
                                                 ------
Options Value                                     50.3
Plus: Other Options/Warrants Value                 0.0
Total Value of Options/Warrants                                 50.3
                                                                -----
EQUITY MARKET VALUE                                           $894.4
Plus: Debt (2)                                   $16.4
Plus: Preferred Stock                              0.0
Plus: Post Ret. and Postemp. Benefits or Min. Int. 0.0
Less: Cash & Equivalents                           2.7
                                                   ----
Net Debt                                                        13.7
                                                               -----
ADJUSTED MARKET VALUE                                         $908.0
- -------------------------------------------------------------------------------


- -------------------------------------------------------------------------------
                        MARKET TRADING MULTIPLES
- -------------------------------------------------------------------------------



                  ADJUSTED MARKET VALUE AS                    MARKET VALUE AS 
                        A MULTIPLE OF:                        A MULTIPLE OF:
              SALES      EBITDA       EBIT      FCF       NET INC.      BOOK VALUE.
              ------     ------       ----      ---       --------      -----------
                                                      
LTM            4.2x      NM             NM       NM        NM            4.3x
1998           3.9x      NM             NM       NM        NM            4.5x
1999           3.7x      NM             NM       NM        NM            4.5x
- -------------------------------------------------------------------------------





- -------------------------------------------------------------------------------
                LTM  CAPITALIZATION AND CREDIT RATIOS
- -------------------------------------------------------------------------------
                         DEBT COVERAGE
EBITDA/INT.       EBIT/INT.           FCF/INT.       DEBT/EBITDA
- -----------       ----------          --------       -----------
                                                 
    NM                NM                 NM               NM
- -------------------------------------------------------------------------------




                            CAPITALIZATION
     BOOK RATIOS                                   MARKET RATIOS
D/E            D/(D+E)                          D/E            D/(D+E)
- ----           -------                          ---            -------
                                                        
7.8%              7.2%                          1.8%             1.8%
- -------------------------------------------------------------------------------


                                                      WASSERSTEIN PERELLA & CO.
- -------------------------------------------------------------------------------




MYCOGEN CORPORATION                                           REVIEW OF MYCOGEN
- -------------------------------------------------------------------------------
MYCOGEN CORP. AFTER ADJUSTMENTS - FINANCIAL SUMMARY ($MM)



- ------------------------------------------------------------------------------------------
                                 1995     1996      1997         LTM    1998 (1)   1999 (1)
FY 8/31                         8/31/95  8/31/96   8/31/97     2/28/98   8/31/98   8/31/99
- ------------------------------------------------------------------------------------------
                                                                 
SALES                           $113.2    $155.6    $211.0      $214.0   $234.5    $247.5
Less: Cost of Sales               67.0      93.5     126.9       127.8       NA        NA
                                ------    ------    ------      ------   ------    ------
Gross Margin                      46.3      62.1      84.1        86.2       NA        NA
Less: S, G & A Expense (3)(4)     61.8      84.6      86.9        93.4       NA        NA
                                ------    ------    ------      ------   ------    ------
EBIT                             (15.5)    (22.6)     (2.8)       (7.3)    (1.5)      0.0
Less: Interest Exp.               (0.9)     (2.4)      1.6         2.9      1.5       1.5
Less: Other Exp. (Inc.)           (0.2)     (0.7)      0.0        (0.1)     0.0       0.0
                                ------    ------    ------      ------   ------    ------
EBT                              (14.4)    (19.5)     (4.4)      (10.0)    (3.0)     (1.5)
Less: Income Tax Exp.              0.0       0.0      13.6        14.7      0.0       0.0
Less: Pref. Div. & Min. Int.       1.5       0.6       0.0         0.0       0.0       0.0
                                ------    ------    ------      ------   ------    ------
NET INCOME (3)(4)                (15.9)    (20.0)    (18.0)      (24.7)     (3.0)     (1.5)
- ------------------------------------------------------------------------------------------
EBIT                            ($15.5)   ($22.6)    ($2.8)      ($7.3)    ($1.5)     $0.0
Plus: Dep. & Amort.                9.0       9.1      10.0        11.6      12.7      13.4
                                ------    ------    ------      ------   ------    ------
EBITDA                            (6.5)    (13.5)      7.2         4.3      11.2      13.4
Less: Capital Exp.                 6.6      13.9      35.7        36.0      39.5      41.7
                                ------    ------    ------      ------   ------    ------
FREE CASH FLOW                   (13.1)    (27.4)    (28.5)      (31.7)    (28.3)    (28.3)
- ------------------------------------------------------------------------------------------


- ------------------------------------------------------------------------------------------
                                       MARGINS
- ------------------------------------------------------------------------------------------
GROSS MARGIN                      40.9%     39.9%     39.9%      40.3%       NA        NA
EBITDA                            -5.8%     -8.7%      3.4%       2.0%      4.8%     5.4%
EBIT                             -13.7%    -14.5%     -1.3%      -3.4%     -0.6%     0.0%
NET INCOME                       -14.1%    -12.9%     -8.5%     -11.6%     -1.3%    -0.6%
FREE CASH FLOW                   -11.6%    -17.6%    -13.5%     -14.8%    -12.1%   -11.4%
- ------------------------------------------------------------------------------------------


- ------------------------------------------------------------------------------------------
                                       RATIOS
- ------------------------------------------------------------------------------------------
Book Value                           -    $181.2    $157.2     $210.2    $207.9    $206.4
RET. ON BOOK EQUITY (ROE)            -     -11.1%    -11.5%     -11.8%     -1.4%     -0.7%
Total Book Assets                    -     227.5     239.7      292.8        NA        NA
RET. ON BOOK ASSETS (ROA)            -      -9.5%     -7.1%      -7.9%       NA        NA
- ------------------------------------------------------------------------------------------







- ------------------------------------------------------------------------------------------
                               MARKET CAPITALIZATION
- ------------------------------------------------------------------------------------------
                                                                          
STOCK PRICE (6/22/98)                                                           $23.38
 52-WEEK HIGH/LOW: $25.50/$15.88
Shares Outstanding -  MYCO                                                       36.11
                                                                                ------
PRE-DILUTED EQUITY MARKET VALUE                                                 $844.1
- ------------------------------------------------------------------------------------------

Pre-Diluted Equity Market Value                                                 $844.1
Options Outstanding                                             4.4
Average Strike Price                                         $12.03
                                                             ------
Options Value                                                  50.3
Plus: Other Options/Warrants Value                              0.0
Total Value of Options/Warrants                                                   50.3
                                                                                  ----
EQUITY MARKET VALUE                                                             $894.4
Plus: Debt(2)                                                 $16.4
Plus: Preferred Stock                                           0.0
Plus: Post Ret. and Postemp Benefits or Min. Int.               0.0
Less: Cash & Equivalents                                        2.7
                                                             ------
Net Debt                                                                          13.7
                                                                                  ----
ADJUSTED MARKET VALUE                                                           $908.0
- ------------------------------------------------------------------------------------------



- --------------------------------------------------------------------------------
                             MARKET TRADING MULTIPLES
- --------------------------------------------------------------------------------


                            Adjusted Market Value as                   Market Value as
                                 a multiple of:                         a multiple of
                     SALES       EBITDA     EBIT        FCF          NET INC.   BOOK VAL.
                     -----       ------     ----        ---          --------   ---------
                                                              
LTM                   4.2x         NM        NM         NM            NM           4.3x
1998                  3.9x         NM        NM         NM            NM           4.3x
1999                  3.7x         NM        NM         NM            NM           4.3x
- ------------------------------------------------------------------------------------------



- -------------------------------------------------------------------------------
                         LTM CAPITALIZATION AND CREDIT RATIOS
- -------------------------------------------------------------------------------


                                     DEBT COVERAGE
   EBITDA/INT.           EBIT/INT.               FCF/INT.         DEBT/EBITDA
   -----------           ---------               --------         -----------
                                                         
      1.5x                  NM                     NM                 3.8x
- ------------------------------------------------------------------------------------------


- --------------------------------------------------------------------------------



                                    CAPITALIZATION
             BOOK RATIOS                                       MARKET RATIOS
        --------------------                                --------------------
        D/E          D/(D+E)                                D/E          D/(D+E)
        ---          -------                                ---          -------
                                                                
        7.8%           7.2%                                 1.8%           1.8%
- ------------------------------------------------------------------------------------------


- ----------------------------
FOOTNOTES
- ----------------------------
(1) Next fiscal year results are based upon Furman Selz research report as of 
    3/1/98
(2) Book value of debt assumed to approximate market value
(3) Excludes other charges of $27.6MM and $31.7MM (impairment of facilities 
    and costs to exit those facilities, severance, patent litigation fees, 
    acquired in-process technology and equity in net loss of investees) in
    1996 and 1997, respectively (tax-effected at 38%)
(4) Excludes litigation expenses of $11.0MM projected by analysts in 1998E

                                                     WASSERSTEIN PERELLA & CO.
- ------------------------------------------------------------------------------



MYCOGEN CORPORATION                                           REVIEW OF MYCOGEN
- -------------------------------------------------------------------------------
STOCK PRICE AND VOLUME HISTORY FOR LAST TWO YEARS

                  Weekly from June 22, 1996 to June 22, 1998

MYCO       MYCOGEN CORP




            Closing       Daily
              Price      Volume
                   
 7/19/96     15.500        19.9
 7/26/96     15.250        38.3
 8/02/96     15.652        11.7
 8/09/96     14.750        13.3
 8/16/96     17.000       176.1
 8/23/96     16.000        39.6
 8/30/96     15.938        19.4
 9/06/96     16.250        29.9
 9/13/96     14.250        40.0
 9/20/96     14.250        13.1
 9/27/96     14.500        13.1
10/04/96     14.250        18.5
10/11/96     14.250        96.5
10/18/96     14.250        20.2
10/25/96     15.500        73.8
11/01/96     15.750        79.7
11/08/96     15.750         9.7
11/15/96     17.000       168.7
11/22/96     16.250       287.3
11/29/96     16.750        19.1
12/06/96     19.000        72.9
12/13/96     24.000       288.9
12/20/96     21.500        30.3
12/27/96     21.750        21.0
 1/03/97     24.000       172.9
 1/10/97     23.750       251.4
 1/17/97     27.750       251.6
 1/24/97     24.625        53.9
 1/31/97     25.500       137.0
 2/07/97     26.500       105.1
 2/14/97     26.125        19.3
 2/21/97     25.750        32.8
 2/28/97     26.125        40.8
 3/07/97     27.000        27.0
 3/14/97     27.250        57.7
 3/21/97     25.750        37.6
 3/27/97     24.750        65.0
 4/04/97     19.250       157.9
 4/11/97     18.125        33.6
 4/18/97     18.000       152.9
 4/25/97     18.750         9.4
 5/02/97     21.125        93.7
 5/09/97     22.000       129.3
 5/16/97     22.000        27.8
 5/23/97     22.250        36.9
 5/30/97     23.500        13.8
 6/06/97     22.750        32.6
 6/13/97     22.750        31.4
 6/20/97     20.000        58.1
 6/27/97     19.125        21.7
 7/03/97     22.000        22.7
 7/11/97     23.375       190.2
 7/18/97     23.000        31.3
 7/25/97     22.625        53.9
 8/01/97     22.125        50.2
 8/08/97     24.625        85.1
 8/15/97     24.000        22.7
 8/22/97     23.500        79.5
 8/29/97     24.750        27.5
 9/05/97     24.500         9.1
 9/12/97     23.938         6.9
 9/19/97     23.188        34.2
 9/26/97     24.125        24.9
10/03/97     23.250        11.1
10/10/97     23.125         8.5
10/17/97     22.938        10.8
10/24/97     20.750       244.0
10/31/97     21.250         6.9
11/07/97     20.750        17.8
11/14/98     19.938         4.1
11/21/97     19.875         7.0
11/28/97     19.500         3.6
12/05/97     19.875        35.3
12/12/97     19.750        19.1
12/19/97     19.125         9.0
12/26/97     18.500         5.6
 1/02/98     19.125        10.8
 1/09/98     19.125        47.6
 1/16/98     21.750        44.9
 1/23/98     18.875        39.2
 1/30/98     20.625         9.1
 2/06/98     16.625        31.6
 2/13/98     20.625       409.9
 2/20/98     20.000       100.4
 2/27/98     17.000        94.8
 3/06/98     18.750        60.5
 3/13/98     18.500        13.3
 3/20/98     20.250       122.8
 3/27/98     18.250       136.1
 4/03/98     18.250        65.1
 4/09/98     18.250        51.2
 4/17/98     19.000        10.2
 4/24/98     20.000        36.2
 5/01/98     22.813       532.5
 5/08/98     23.563        52.3
 5/15/98     23.625        53.4
 5/22/98     24.250        53.8
 5/29/98     23.625        39.8
 6/05/98     24.625        68.5
 6/12/98     22.750       206.8
 6/19/98     23.563        59.4
 6/26/98     23.250        65.3
 7/02/98     23.875       152.2
 7/10/98     24.125        50.7


                                                     WASSERSTEIN PERELLA & CO.
- ------------------------------------------------------------------------------


MYCOGEN CORPORATION                                           REVIEW OF MYCOGEN
- -------------------------------------------------------------------------------
INDEXED STOCK PRICE HISTORY SINCE 1996




Date               Mycogen   Dow Chemical   S&P 500   Russell 2000    Peer
- ----               -------   ------------   -------   ------------    ----
                                                      
12/29/95           100.00    100.00         100.00       100.00       100.00
1/05/96             86.76    103.56         100.13        98.80        95.94
1/12/96             94.12    100.71          97.71        96.57        97.13
1/19/96             92.65     98.40          99.33        96.62        97.33
1/26/96             92.65    101.70         100.92        98.50        98.07
2/02/96             95.59    105.34         103.23       100.55       105.37
2/09/96            102.94    111.03         106.57       101.63       107.90
2/16/96            113.24    107.47         105.20       101.78       107.97
2/23/96            113.24    113.35         107.01       103.10       110.20
3/01/96            113.24    113.52         104.62       102.57       112.99
3/08/96            104.41    116.01         102.85       101.03       115.43
3/15/96            112.50    126.33         104.14       102.88       117.19
3/22/96            101.47    123.31         105.63       104.28       120.77
3/29/96            101.47    123.84         104.80       104.68       122.51
4/04/96            100.00    125.27         106.48       105.95       124.04
4/12/96             97.06    124.73         103.37       104.81       125.61
4/19/96            102.94    127.76         104.73       107.13       143.51
4/26/96            102.94    124.56         106.09       110.08       146.59
5/03/96             98.53    130.78         104.17       109.77       139.44
5/10/96            105.88    125.44         105.87       111.13       139.80
5/17/96            105.88    121.35         108.60       114.13       144.01
5/24/96            105.15    121.89         110.16       115.39       139.10
5/31/96            107.35    119.04         108.64       114.52       137.96
6/07/96            104.41    116.90         109.32       113.57       135.84
6/14/96            104.41    116.19         108.10       112.38       133.41
6/21/96            102.21    113.70         108.27       109.25       122.44
6/28/96             88.24    108.19         108.88       109.70       132.31
7/05/96             86.76    109.25         106.74       107.54       126.02
7/12/96             79.41    111.92         104.91       102.44       119.06
7/19/96             91.18    103.56         103.70       101.76       107.41
7/26/96             88.71    104.98         103.24        99.56       105.72
8/02/96             91.91    107.12         107.56       102.67       111.19
8/09/96             86.76    110.14         107.50       103.63       108.10
8/16/96            100.00    112.46         108.00       104.10       105.65
8/23/96             94.12    113.70         108.30       105.00       110.56
8/30/96             93.75    113.52         105.85       105.67       108.04
9/06/96             95.59    113.17         106.45       105.74       106.36
9/13/96             83.82    114.95         110.49       107.86       111.80
9/20/96             83.82    117.08         111.54       108.50       109.51
9/27/96             85.29    115.12         111.41       109.35       112.98
10/04/96            83.82    114.59         113.89       110.55       132.75
10/11/96            83.82    112.46         113.76       110.10       132.71
10/18/96            83.82    112.10         115.41       110.09       137.07
10/25/96            91.18    111.57         113.80       108.55       130.24
11/01/96            92.65    111.57         114.26       107.53       129.10
11/08/96            92.65    114.23         118.65       109.05       132.13
11/15/96           100.00    119.75         119.76       109.67       128.49
11/22/96            95.59    117.44         121.56       110.74       125.41
11/29/96            98.53    119.22         122.91       112.07       126.64
12/06/96           111.76    116.37         120.08       112.51       129.14
12/13/96           141.18    113.17         128.30       112.09       127.73
12/20/96           126.47    113.70         121.58       112.89       132.32
12/27/96           127.94    112.46         122.87       113.67       131.09
1/03/97            141.18    114.06         121.45       114.52       124.29
1/10/97            139.71    117.79         123.31       115.86       129.21
1/17/97            163.24    117.97         126.02       116.43       136.78
1/24/97            144.85    112.63         125.10       116.51       137.14
1/31/97            150.00    109.79         127.64       116.93       136.39
2/07/97            155.88    112.63         128.19       116.07       131.98
2/14/97            153.68    114.77         131.26       116.82       140.11
2/21/97            151.47    112.81         130.17       115.95       138.29
2/28/97            153.68    115.30         128.39       113.95       135.89
3/07/97            158.82    117.97         130.69       115.66       136.36
3/14/97            160.29    118.51         128.78       114.26       133.07
3/21/97            151.47    117.97         127.30       111.32       127.18
3/27/97            145.59    114.23         125.64       110.44       122.04
4/04/97            113.24    112.63         123.05       107.88       117.99
4/11/97            106.62    112.63         119.76       107.37       113.63
4/18/97            105.88    114.59         124.42       108.16       121.16
4/25/97            110.29    114.59         124.26       106.29       119.95
5/02/97            124.26    120.64         131.99       112.03       129.62
5/09/97            129.41    125.09         133.91       114.38       132.57
5/16/97            129.41    124.38         134.71       115.61       139.50
5/23/97            130.88    120.46         137.52       118.89       147.39
5/30/97            138.24    118.68         137.72       120.51       146.79
6/06/97            133.82    120.11         139.30       122.52       150.55
6/13/97            133.82    126.69         145.03       124.08       154.09
6/20/97            117.65    125.80         145.91       124.57       166.68
6/27/98            112.50    125.36         144.06       124.23       169.65
7/03/97            129.41    125.27         148.87       125.38       169.41
7/11/97            137.50    128.91         148.83       127.31       173.01
7/18/97            135.29    128.02         148.60       128.46       170.47
7/25/97            133.09    128.02         152.42       129.30       175.23
8/01/97            130.15    133.90         153.77       131.09       178.40
8/08/97            144.85    132.56         151.57       131.09       195.38
8/15/97            141.18    130.96         146.25       129.31       188.34
8/22/97            138.24    127.85         149.94       131.57       190.51
8/29/97            145.59    125.98         146.03       134.01       188.11
9/05/97            144.12    122.86         150.84       137.05       185.99
9/12/97            140.81    126.25         150.00       139.28       185.01
9/19/97            136.40    131.49         154.32       141.52       194.22
9/26/97            141.91    128.74         153.46       142.06       186.61
10/03/97           136.76    132.38         156.68       145.43       195.80
10/10/97           136.03    128.65         157.00       147.18       213.86
10/17/97           134.93    128.11         153.29       142.19       205.02
10/24/97           122.06    131.05         152.88       141.64       205.02
10/31/97           125.00    129.00         148.49       137.12       199.15
11/07/97           122.06    128.38         150.59       137.74       197.27
11/14/97           117.28    131.94         150.72       135.59       202.64
11/21/97           116.91    140.30         156.36       137.69       208.25
11/28/97           114.71    140.57         155.12       136.06       204.61
12/05/97           116.91    143.42         159.72       138.64       208.73
12/12/97           116.18    138.79         154.79       133.76       216.80
12/19/97           112.50    137.54         153.72       132.93       233.41
12/26/97           108.82    140.93         152.04       133.40       236.39
1/02/98            112.50    143.42         158.30       138.15       238.63
1/09/98            112.50    132.74         150.62       130.69       234.51
1/16/98            127.94    130.16         156.11       134.90       237.30
1/23/98            111.03    127.67         155.47       134.45       231.59
1/30/98            121.32    128.11         159.15       136.10       233.17
2/06/98             97.79    132.38         164.38       140.99       231.29
2/13/98            121.32    127.49         165.62       143.78       233.84
2/20/98            117.65    127.76         167.91       143.68       239.18
2/27/98            100.00    130.25         170.37       146.16       253.30
3/06/98            110.29    129.89         171.40       146.76       274.53
3/13/98            108.82    130.52         173.50       148.36       300.36
3/20/98            119.12    137.90         178.46       150.09       299.39
3/27/98            107.35    135.50         177.85       151.01       286.42
4/03/98            107.35    134.16         182.28       153.75       289.14
4/09/98            107.35    137.54         180.32       151.93       281.63
4/17/98            111.76    141.46         182.28       154.13       275.38
4/24/98            117.65    139.41         179.87       152.01       272.16
5/01/98            134.19    140.04         182.00       153.48       293.81
5/08/98            138.60    139.50         179.91       151.75       307.46
5/15/98            138.97    139.15         180.01       149.52       294.36
5/22/98            142.65    139.59         180.29       146.53       290.90
5/29/98            138.97    137.90         177.10       144.51       291.63
6/05/98            144.85    142.26         180.84       143.76       315.28
6/12/98            133.82    138.52         178.40       139.76       309.82
6/19/98            138.60    135.23         178.70       138.77       330.38
6/26/98            136.76    137.19         183.98       142.50       319.47
7/02/98            140.44    137.63         186.13       145.05       313.28
7/10/98            141.91    135.94         189.04       145.09       295.63


             WEEKLY FROM JANUARY 1, 1996 TO JUNE 22, 1998

- -------------------------
(1) Includes Pioneer Hi-Bred, Delta & Pine Land and Agribiotech





                                                      WASSERSTEIN PERELLA & CO.
- -------------------------------------------------------------------------------



MYCOGEN CORPORATION                                           REVIEW OF MYCOGEN
- -------------------------------------------------------------------------------
INDEXED PRICE HISTORY FOR LAST FIVE YEARS




     A graph appears here showing the monthly changes in relative stock 
     prices of Mycogen Corporation, The Dow Chemical Company and the Standard 
     & Poor's 500 Stock Index beginning on June 22, 1993, and ending on 
     June 22, 1998, with each stock beginning at a baseline of 100.










                                                      WASSERSTEIN PERELLA & CO.
- -------------------------------------------------------------------------------



MYCOGEN CORPORATION                                          REVIEW OF MYCOGEN
- ------------------------------------------------------------------------------
SHAREHOLDER PROFILE
($ IN MILLIONS, SHARES IN THOUSANDS)




                                                           MARKET VALUE
                                                 SHARES    AS OF 6/22/98   % HELD
                                                 ------    -------------   ------
                                                                  
5% OWNERS
- ---------
  Dow AgroSciences                              24,917.0       $582.4        61.5% (1)
  State of Wisconsin Investment Board            1,800.5         42.1         4.4%
                                                --------       ------       ------
  TOTAL                                         26,717.5       $624.5        65.9%

OFFICERS, DIRECTORS AND EMPLOYEES
- ---------------------------------
  Officers                                       1,668.6        $39.0         4.1% (2)
  Outside Directors (excl. Dow AgroSciences 
   directors)                                       22.5          0.5         0.1% (3)
  Other (incl. Employees)                        5,433.2        127.0        13.4% (4)
                                                --------       ------       ------
  TOTAL                                          7,124.3       $166.5        17.6%

INSTITUTIONS
- ------------
  Primecap Management Company                    1,736.0        $40.6         4.3%
  Capital Research & Management Co.              1,700.0        $39.7         4.2%
  College Retirement Equities Fund (TIAA-CREF)     379.1         $8.9         0.9%
  Barclays Global Advisors                         309.9         $7.2         0.8%
  Dimensional Fund Advisors                        224.5          5.2         0.6%
  U.S. Trust Co.                                   147.0          3.4         0.4%
  Texas Teachers' Retirement System                125.0          2.9         0.3%
  Kentucky Employees Retirement System             111.0          2.6         0.3%
  Tirschwell & Loewy, Inc.                         104.0          2.4         0.3%
  Ohio State Teacher's Retirement                  101.0          2.4         0.2%
  Vanguard Group                                   101.0          2.4         0.2%
  Other                                            833.2         19.5         2.1%
                                                --------       ------       ------
  TOTAL                                          5,871.6       $137.2        14.5%

TOTAL INSTITUTIONS, INSIDERS AND BENEFICIAL 
 HOLDERS                                        39,713.4       $928.3        97.9%
  Other Shareholders                               831.9         19.4         2.1%
                                                --------       ------       ------
CURRENT TOTAL SHARES OUTSTANDING                40,545.3       $947.7       100.0% (5)
                                                --------       ------       ------
                                                --------       ------       ------



- --------------------------------
Sources: CDA Spectrum dated 6/22/98, proxy dated 1/8/98, public filings and 
         management
(1) Includes 150,834 options outstanding
(2) Includes 1,512,834 options outstanding
(3) Includes 22,500 options outstanding
(4) Includes 1,948,983 options outstanding
(5) Includes 4,435,990 options outstanding

                                                     WASSERSTEIN PERELLA & CO.
- ------------------------------------------------------------------------------



MYCOGEN CORPORATION
- -------------------------------------------------------------------------------




                       -----------------------------------




                                REVIEW OF DOW




                       -----------------------------------






                                                      WASSERSTEIN PERELLA & CO.
- -------------------------------------------------------------------------------



MYCOGEN CORPORATION                                               REVIEW OF DOW
- -------------------------------------------------------------------------------
OVERVIEW

- ----------------------
BUSINESS DESCRIPTION   -  THE DOW CHEMICAL COMPANY IS A DIVERSIFIED, WORLDWIDE 
- ----------------------    MANUFACTURER AND SUPPLIER OF CHEMICALS, PLASTICS AND 
                          AGRICULTURAL PRODUCTS
- ----------------------
DOW AGROSCIENCES       -  A WHOLLY-OWNED SUBSIDIARY OF THE DOW CHEMICAL COMPANY 
- ----------------------    THAT PRODUCES AGRICULTURAL PRODUCTS, SUCH AS 
                          BROADSTRIKE HERBICIDES AND DURSBAN AND LORSBAN 
                          INSECTICIDES, USED IN CROP PROTECTION AND INDUSTRIAL 
                          PEST CONTROL

                          -  Created in 1997 after Dow acquired Eli Lilly and 
                             Company's 40% share in DowElanco, which was then 
                             renamed Dow AgroSciences. The purchase price of 
                             $900 million was approximately 1.13x sales

                          -  Recent product launches include Tracer and Success 
                             insect control products in the U.S. and Fortress 
                             fungicide in Europe

                          -  Will incorporate the agricultural products 
                             business of Sanachem through Dow's acquisition of 
                             Sentrachem in late 1997. Sanachem is the world's 
                             third largest manufacturer of generic crop 
                             protection and pest control products with 
                             approximately $200 million in annual sales
- ----------------------
FACILITIES             -  OPERATES 114 MANUFACTURING SITES IN 33 COUNTRIES
- ----------------------

- ----------------------
HEADQUARTERS           -  MIDLAND, MICHIGAN
- ----------------------

- ----------------------
STATE OF INCORPORATION -  DELAWARE
- ----------------------


                                                       WASSERSTEIN PERELLA & CO.
- --------------------------------------------------------------------------------






MYCOGEN CORPORATION                                                                               REVIEW OF DOW
- ---------------------------------------------------------------------------------------------------------------
THE DOW CHEMICAL CO. - FINANCIAL SUMMARY ($MM)

- ---------------------------------------------------------------------------------------------------------------
                                          1995            1996            1997             LTM         NFY (1)
FY12/31                               12/31/95        12/31/96        12/31/97         3/31/98        12/31/98
- ---------------------------------------------------------------------------------------------------------------
                                                                                      
SALES                                $20,200.0       $20,053.0       $20,018.0       $19,855.0       $18,899.0

Less: Cost of Sales                   13,337.0        14,108.0        14,679.0        14,755.0        13,059.0
                                      --------        --------        --------        --------        --------
Gross Margin                           6,863.0         5,945.0         5,339.0         5,100.0         5,840.0

Less: S, G & A Expense                 2,972.0         2,858.0         2,613.0         2,583.0         3,700.0
                                       -------         -------         -------         -------         -------
EBIT                                   3,891.0         3,087.0         2,726.0         2,517.0         2,140.0

Less: Interest Exp.                      145.0           208.0           277.0           380.0           480.0

Less: Other Exp. (Inc.)                  217.0          (409.0)         (499.0)         (499.0)         (468.0)
                                         -----          ------          ------          ------          ------
EBT                                    3,529.0         3,288.0         2,948.0         2,636.0         2,128.0

Less: Income Tax Exp.                  1,442.0         1,187.0         1,041.0           924.4           776.0

Less: Pref. Div. & Min. Int.             203.0           201.0           105.0            45.0             9.0
                                         -----           -----           -----            ----             ---
NET INCOME (3)                         1,884.0         1,900.0         1,802.0         1,666.6         1,343.0
- --------------------------------------------------------------------------------------------------------------

EBIT                                  $3,891.0        $3,087.0        $2,726.0        $2,517.0        $2,140.0

Plus: Dep. & Amort.                    1,442.0         1,298.0         1,287.0         1,254.0         1,185.0
                                       -------         -------         -------         -------         -------
EBITDA                                 5,333.0         4,385.0         4,013.0         3,771.0         3,325.0

Less: Capital Exp.                     1,417.0         1,344.0         1,198.0         1,254.0         1,650.0
                                       -------         -------         -------         -------         -------
FREE CASH FLOW                         3,916.0         3,041.0         2,815.0         2,517.0         1,675.0
- --------------------------------------------------------------------------------------------------------------




- --------------------------------------------------------------------------------------------------------------
                                                    MARGINS
- --------------------------------------------------------------------------------------------------------------
                                                                                          
GROSS MARGIN                             34.0%           29.6%           26.7%           25.7%           30.9%

EBITDA                                   26.4%           21.9%           20.0%           19.0%           17.6%

EBIT                                     19.3%           15.4%           13.6%           12.7%           11.3%

NET INCOME                                9.3%            9.5%            9.0%            8.4%            7.1% 

FREE CASH FLOW                           19.4%           15.2%           14.1%           12.7%            8.9% 
- --------------------------------------------------------------------------------------------------------------




- --------------------------------------------------------------------------------------------------------------
                                                    RATIOS
- --------------------------------------------------------------------------------------------------------------
                                                                                      

Book Value                                   -        $7,954.0        $7,626.0        $7,806.0        $7,960.0

RET. ON BOOK EQUITY (ROE)                    -          23.9%           23.6%           21.4%           16.9%

Total Book Assets                            -        24,673.0        24,040.0        23,524.0        24,311.0

RET. ON BOOK ASSETS (ROA)                    -           8.2%            8.2%            8.1%            6.7%
- --------------------------------------------------------------------------------------------------------------




- ---------------------------------------------------------------------------------
                                 MARKET CAPITALIZATION
- ---------------------------------------------------------------------------------
                                                                 
STOCK PRICE (6/22/98)                                                      $94.19
    52-WEEK HIGH/LOW:  $102.63/$84.75
Shares Outstanding -  DOW                                                  225.12
                                                                           ------
PRE-DILUTED EQUITY MARKET VALUE                                         $21,203.9
- ---------------------------------------------------------------------------------

Pre-Diluted Equity Market Value                                         $21,203.9

Options Exercisable                                       8.7

Average Strike Price                                   $63.84
                                                       ------
Options Value                                           262.6

Plus: Other Options/Warrants Value                       23.5

Total Value of Options/Warrants                                             286.0
                                                                            -----
EQUITY MARKET VALUE                                                     $21,490.0

Plus: Debt(2)                                        $5,621.0

Plus: Preferred Stock                                   120.0

Plus: Post Ret. and Postemp. Benefits or Min. Int.    2,259.0

Less: Cash & Equivalents                                537.0
                                                        -----
Net Debt                                                                  7,463.0
                                                                          -------
ADJUSTED MARKET VALUE                                                   $28,953.0
- ---------------------------------------------------------------------------------




- ---------------------------------------------------------------------------------
                           MARKET TRADING MULTIPLES
- ---------------------------------------------------------------------------------
                         Adjusted Market Value as             Market Value as
                              a multiple of:                   a multiple of:

               Sales     EBITDA        EBIT       FCF        Net Inc.  Book Val.
               -----     ------        ----       ---        --------  ---------
                                                     
LTM             1.5x       7.7x        11.5x      11.5x       12.9x      2.8x

NFY             1.5x       8.7x        13.5x      17.3x       16.0x      2.7x
- ---------------------------------------------------------------------------------




- ---------------------------------------------------------------------------------
                     LTM CAPITALIZATION AND CREDIT RATIOS
- ---------------------------------------------------------------------------------
                               DEBT COVERAGE

        EBITDA/Int.         EBIT/Int.           FCF/Int.       Debt/EBITDA
        -----------         ---------           --------       -----------
                                                      
            9.9x               6.6x                6.6x            1.5x
- ---------------------------------------------------------------------------------

                               CAPITALIZATION
                 BOOK RATIOS                     MARKET RATIOS
             D/E            D/(D+E)           D/E            D/(D+E) 
             ---            -------           ---            -------
                                                    
            72.0%             41.9%           26.2%            20.7% 

- ---------------------------------------------------------------------------------


- ----------------------------------------
FOOTNOTES
- ----------------------------------------
(1) Next fiscal year results are based upon Morgan Stanley Dean Witter 
    research report as of 4/29/98
(2) Book value of debt assumed to approximate market value
(3) Excludes after-tax income from discontinued operations of $187.0MM in 
    1995, pre-tax non-recurring charges of $668MM and one-time sale of $816MM 
    in 1998 (tax-effected at 40%)

                                                                              
                                                      WASSERSTEIN PERELLA & CO.
- -------------------------------------------------------------------------------



MYCOGEN CORPORATION                 
- -----------------------------------------------------------------------------











                           PRELIMINARY VALUATION 

                                 ANALYSIS












                                                    WASSERSTEIN PERELLA & CO.
- -----------------------------------------------------------------------------



MYCOGEN CORPORATION                 
- -----------------------------------------------------------------------------











                               REVIEW OF ANALYST

                                 PERSPECTIVES












                                                    WASSERSTEIN PERELLA & CO.
- -----------------------------------------------------------------------------



MYCOGEN CORPORATION                 VALUATION: REVIEW OF ANALYST PERSPECTIVES
- -----------------------------------------------------------------------------
EQUITY ANALYST PERSPECTIVE


Six Analyst recommendations:         2 buy, 4 hold

Wide range of forecasts:




                                                              

                                                FY 1998           FY 1999
                                                -------           -------
                                     Hi         ($0.39)           $ 0.15
                                     Mean        (0.51)             0.06
                                     Lo          (0.75)            (0.04)



Negative E.P.S. momentum:            YTD 5 downward revisions, I upward revision



General Issues:

                -  Outlook for conventional seed business
                
                -  Bt dependency

                -  Diffuse nature of R & D program




                                                    WASSERSTEIN PERELLA & CO.
- -----------------------------------------------------------------------------



MYCOGEN CORPORATION                 VALUATION: REVIEW OF ANALYST PERSPECTIVES
- -----------------------------------------------------------------------------
OUTLOOK FOR CONVENTIONAL SEED BUSINESS



"...[MYCOGEN'S SEED BUSINESS] SMALL SIZE IS A DETRIMENT,...HIGH SEED DISCARD 
AND OBSOLESCENCE CHARGES AND A HIGHER COST BASE...WE BELIEVE INCREASING THE 
SIZE OF THE MYCOGEN SEED EFFORT IS KEY...HOWEVER...WE QUESTION WHETHER THE 
COMPANY WILL BE ABLE TO FIND SEED OPERATORS OF SUFFICIENT SIZE AND QUALITY."

                         Furman Selz, March 13, 1998

WP&Co. Observations:

     -  Mycogen, over the past three years has increased its presence on the 
N. American corn farmers fields by nearly four-fold.

     -  Mycogen is uniquely positioned to pursue the opportunities to build a 
franchise in the large and growing Latin American market for major row crops. 
Further, while the size and scope of Mycogen's breeding programs are much 
smaller than largest germplasm suppliers, less overlap within Mycogen product 
lines allows keeping a closer relationship of proprietary lines to 
competition. Mycogen'network of 11 breeding stations provides adequate 
diversity of yield, maturity and disease resistance characteristics.

     -  Side-by-side comparisons of Mycogen hybrids show per acre yields 
approaching leading competitors.

     -  Program appears effective, but subject to execution risk of producing 
adequate seed inventory within time, cost and quality constraints. Too early 
to judge efficiency of winter nursery exchange between US/Europe and 
PR/ S. America. Investments in new equipment (combines, tractors, dryers) 
and software (SAP/R3) enhance probability of success.


                                                    WASSERSTEIN PERELLA & CO.
- -----------------------------------------------------------------------------



MYCOGEN CORPORATION                 VALUATION: REVIEW OF ANALYST PERSPECTIVES
- -----------------------------------------------------------------------------
BT DEPENDENCY

"...THE RAPIDLY GROWING ACREAGE OF CORN, COTTON AND POTATOES THAT ARE 
GENETICALLY ENGINEERED TO PRODUCE BT...HIGHLIGHTS FEARS ABOUT EMERGING INSECT 
RESISTANCE.  GENETICALLY ENGINEERED BT CROPS PROVIDE EXPOSURE TO THE TOXINS 
THROUGHOUT THE GROWING SEASON, LEADING TO SELECTION PRESSURES THAT MIGHT 
ENABLE ONLY RESISTANT PESTS TO SURVIVE."
                                        SCIENTIFIC AMERICAN, May 1998


WP&Co. Observations:

- -  Mycogen first company to recognize insect-specific bioactivity of Bt's 
   Portfolio of -50 Bt genes equal to next four competitors combined.

- -  Array of Bt's provides access to multiple products for specific pest/crop 
   situations.  Pest specific products may change the threshold for insect 
   control and justify significant increases in treated acreage.

- -  Cross resistance unlikely since Bt protein structurally diverse; unique 3D 
   configurations form very specific associations with cellular constituents.

- -  Rotation between different Bt's remove selection pressure for resistant 
   pest; fitness requirement restores susceptibility.  Toxin cycling 
   "evergreens" product line.

- -  Bt toxins have been characterized by Mycogen researchers as having 
   specific activity against a wide range of coleopteran, lepidopteran, and 
   even nematode pests making the Bt technology valuable against a broad host 
   of crop applications.

- -  Near to medium term competition to Bt's looks problematic since these 
   proteins are well characterized with a good understanding of the functional 
   genetics and expression.  By comparison, novel toxins face an 8-10 year 
   regulatory and scientific timeline for commercialization.


                                                    WASSERSTEIN PERELLA & CO.
- -----------------------------------------------------------------------------



MYCOGEN CORPORATION                 VALUATION: REVIEW OF ANALYST PERSPECTIVES
- -----------------------------------------------------------------------------
BT DEPENDENCY (CONTINUED)

- -  Program appears logical and defensible, but suffers from execution risk:  
   Manpower commitments for developing novel transgenics are quite modest at 
   both Pioneer and at Mycogen and there appears to be little effort underway 
   to stack Bt genes in multiple trait products: Mycogen currently markets a 
   single Bt cultivar and no second generation Bt product is projected to be 
   available prior to 2001.

- -  While emphasizing the development of Bt-based plant products, Mycogen has 
   created a sizable array of promoters, expression systems, and experience 
   relevant to expression of any transgene in plants.  This competency in 
   regulating exogenous gene expression would be valuable to any other 
   research program as it nears commercialization (e.g. Ahlquist Technology). 
   Clearly, it is of value to any competitor desiring to shorten time to 
   market of its own products as illustrated by Monsonto's repeated requests 
   to gain access to Mycogen's proprietary Ub-1 promoter.


                                                    WASSERSTEIN PERELLA & CO.
- -----------------------------------------------------------------------------



MYCOGEN CORPORATION                 VALUATION: REVIEW OF ANALYST PERSPECTIVES
- -----------------------------------------------------------------------------

DIFFUSE NATURE OF R & D PROGRAM


Mycogen has significant commitments to six distinct R & D efforts:

       Input traits                   Oral immunity

       Output traits                  Ahlquist technology

       Disease resistance             fermentation



WP&Co. Observations:

- -  Large multinationals with enormous financial resources have generally 
   prioritized around a single program:

       Monsanto/input

       DuPont/output

       Zeneca/disease resistance

- -  Agbiotech competition may rapidly transition from critical mass to scale, 
   isolating Mycogen's modest efforts.

- -  Technological developments may leapfrog Mycogen's position and render its 
   intellectual property obsolescent.  Genechip systems, combinatorial 
   chemistry and high throughput screening have already proven their utility 
   in human drug development.  These technologies can likely be adapted for 
   agbiotech applications:

   -  Use DNA microarrays for "directed evolution"

   -  Use retroviral vectors to immortalize insect gut cells as the basis for 
      a high volume assay.

                                                    WASSERSTEIN PERELLA & CO.
- -----------------------------------------------------------------------------



MYCOGEN CORPORATION                 
- -----------------------------------------------------------------------------











                           VALUATION: DISCOUNTED CASH

                               FLOW ANALYSIS (DCF)












                                                    WASSERSTEIN PERELLA & CO.
- -----------------------------------------------------------------------------



MYCOGEN                                                VALUATION: DCF ANALYSIS
- ------------------------------------------------------------------------------
BUSINESS FINANCIAL PROJECTION METHODOLOGY




- ------------------------------------------------                  -------------------------------------------
             10-YEAR PROJECTIONS                                              DETAILED BASIS
- ------------------------------------------------                  -------------------------------------------
                                                               
                                                                  -------------------------------------------
                                                                  - Includes demographic factors and regional
             Target Crop Acreage                                    analysis by crop
                      X                                           - Shifting planting patterns
                                                                  -------------------------------------------
                                                                  -------------------------------------------
                                                                  - Adoption value of Bt and output modified
Market Penetration of Genetically Modified Seeds                    seed
                      X                                           - Presence on farmers fields
                                                                  -------------------------------------------
                                                                  -------------------------------------------
                                                                  - Preferred penetration in existing base
       Market Share of Mycogen Product                            - Access to partners with large share of new
                      X                                             markets
                                                                  -------------------------------------------
        Mycogen Product Selling Price                             -------------------------------------------
                      =                                           - Value capture based on improved
      Mycogen Product Sales Projections                             productivity and competitive advantage
                      -                                           -------------------------------------------
                                                                  -------------------------------------------
                                                                  - Costs reflect minimal additional COGs and
                                                                    SGA for traits above those for conventional
      Fixed and Variable Costs and Taxes                            seed
                      +                                           - R&D investment accelerated to ensure
                                                                    success timing of products
                                                                  -------------------------------------------
                                                                  -------------------------------------------
   Cash Flow Impact (- W.I. - CapEx + Dep.)                       - Based on current inventory and accounts
                      =                                             payable/recievable trends
       Mycogen Product Free Cash Flow                             - Additional plant expenditure is depending
                                                                    on sales levels and existing capacity
                                                                  -------------------------------------------
                     |
                     |
                     V
        ----------------------------
            VALUATION METHODOLOGY
        ----------------------------



                                                     WASSERSTEIN PERELLA & CO.
- ------------------------------------------------------------------------------



MYCOGEN                                                VALUATION: DCF ANALYSIS
- ------------------------------------------------------------------------------
BAR CHART OF VALUATION METHODOLOGY


- --------------
TERMINAL VALUE:
EBIT MULTIPLES
- --------------

6X - 12X

- -Lower risk established or  
 growing businesses        
- -Includes conventional seed, Soil Sen,
 Biopesticides, AC Humko,   
 and VMO                    
- -Suitable for established 
 or mature businesses 

- -------------
DISCOUNT RATE
- -------------

10% - 20%

- -Lower risk established or  
 growing businesses        
- -Includes conventional seed, Soil Sen,
 Biopesticides, AC Humko,   
 and VMO                    

25% - 45%

- -Higher-risk output trait   
 improvement business       
- -Lower growth rate reflects 
 early stages in            
 commercialization of new   
 technology                 

20% - 30%

- -Developing                 
 Bt/Herbicide-resistance    
 businesses based on new    
 products and established   
 but rapidly improving      
 technology                 

40% - 60%

- -New relatively untested     
 technology-based products.  
 Large growth potential      
 offset by high risk        
- -Risk-adjusted cost-of-capital

- -----------------
TERMINAL VALUE:  
FREE CASH GROWTH 
- -----------------

1% - 2.5%

- -Higher-risk output trait   
 improvement business       
- -Lower growth rate reflects 
 early stages in            
 commercialization of new   
 technology                 

8% - 14%

- -Developing                 
 Bt/Herbicide-resistance    
 businesses based on new    
 products and established   
 but rapidly improving      
 technology                 

25% - 30%

- -New relatively untested     
 technology-based products.  
 Large growth potential      
 offset by high risk        


- -Suitable for growing businesses in take-off phase


                                                      WASSERSTEIN PERELLA & CO.
- -------------------------------------------------------------------------------



MYCOGEN                             VALUATION: DCF ANALYSIS-BRAZIL MODEL EXAMPLE
- --------------------------------------------------------------------------------
BRAZIL INCOME STATEMENT PROJECTIONS ($MM)




                                         1998     1999     2000     2001     2002     2003     2004     2005     2006     2007
                                       -------- -------- -------- -------- -------- -------- -------- -------- -------- --------
                                                                                       
Revenues   Conventional Seeds             $52.8    $65.7    $79.6    $94.6   $104.9   $113.4   $128.4   $156.5   $173.1   $190.3
           Early Traits                    $0.0     $0.0     $0.0     $0.0     $0.6     $4.4    $11.0    $26.3    $43.5    $57.1
           Output Traits                   $0.0     $0.0     $0.0     $0.0     $0.6     $1.9     $4.6     $8.8    $31.3    $65.8
           Disease Resistance              $0.0     $0.0     $0.0     $0.0     $0.0     $0.0     $0.0     $0.0     $0.2     $0.4
                   Total Revenues         $52.8    $65.7    $79.6    $94.6   $106.1   $119.7   $144.1   $191.7   $248.1   $313.6
COGS       Conventional Seeds             $26.4    $32.8    $39.6    $47.0    $52.0    $56.1    $63.4    $77.2    $85.2    $93.5

GROSS PROFIT                              $26.4    $32.9    $39.9    $47.6    $54.1    $63.6    $80.6   $114.5   $162.9   $220.1

SG&A       Conventional Seeds             $13.7    $15.6    $17.1    $18.2    $17.8    $19.3    $21.8    $26.6    $29.4    $32.4
R&D        Conventional Seeds              $3.2     $4.6     $6.4     $8.5    $10.5    $11.3    $12.8    $15.7    $17.3    $19.0
           Early Traits                    $0.6     $2.1     $2.7     $3.3     $3.3     $2.9     $2.9     $2.5     $4.2     $5.4
           Output Traits                   $0.4     $1.4     $2.3     $2.6     $1.7     $2.1     $2.3     $0.9     $4.3     $9.1
           Disease Resistance              $0.0     $0.2     $0.5     $0.3     $0.2     $0.6     $0.6     $0.0     $0.0     $0.0
                   Total R&D               $4.2     $8.3    $11.9    $14.7    $15.7    $17.0    $18.6    $19.1    $25.8    $33.6

EDITDA                                     $8.5     $9.0    $10.9    $14.6    $20.5    $27.3    $40.2    $68.8   $107.7   $154.2
Depreciation                               $1.7     $1.9     $2.2     $2.4     $2.6     $2.7     $3.0     $3.5     $3.8     $4.1
Amortization                               $0.4     $0.4     $0.4     $0.4     $0.4     $0.4     $0.4     $0.4     $0.4     $0.4
EBIT                                       $6.4     $6.7     $8.4    $11.8    $17.5    $24.2    $36.8    $64.9   $103.5   $149.7
Contract and Other Revenue                 $0.0     $0.0     $0.0     $0.0     $0.0     $0.0     $0.0     $0.0     $0.0     $0.0
                                       -------- -------- -------- -------- -------- -------- -------- -------- -------- --------

TOTAL OPERATING INCOME                     $6.4     $6.7     $8.4    $11.8    $17.5    $24.2    $36.8    $64.9   $103.5   $149.7
Taxes (based on BU's)                      (2.4)    (3.4)    (4.6)    (6.0)    (7.1)    (8.4)   (12.5)   (21.4)   (34.2)   (49.4)
Taxes (@ 33%)                              (2.1)    (2.2)    (2.8)    (3.9)    (5.8)    (8.0)   (12.1)   (21.4)   (34.2)   (49.4)
NET INCOME                                  4.3      4.5      5.6      7.9     11.7     16.2     24.6     43.5     69.3    100.3


Tax Advantage                              (0.3)    (1.2)    (1.8)    (2.1)    (1.3)    (0.4)   (0.3)




                                                       WASSERSTEIN PERELLA & CO.
- --------------------------------------------------------------------------------



MYCOGEN                           VALUATION: DCF ANALYSIS - BRAZIL MODEL EXAMPLE
- --------------------------------------------------------------------------------
BRAZIL CORN FINANCIAL ASSUMPTIONS ($MM, EXCEPT PER UNIT PRICE AND UNITS IN 
OOOS)




                                         1998     1999     2000     2001     2002     2003     2004     2005     2006     2007
                                       -------- -------- -------- -------- -------- -------- -------- -------- -------- --------
                                                                                       
INCOME STATEMENT ASSUMPTIONS
Total Market in Hectors                 12,000   12,500   13,000   13,500   14,000   14,200   14,400   14,600   14,800   15,000
Mycogen % of Market Share                11.0%    13.0%    15.0%    17.0%    18.0%    19.0%    21.0%    25.0%    27.0%    29.0%
                                       -------- -------- -------- -------- -------- -------- -------- -------- -------- --------
Mycogen Units                            1,320    1,625    1,950    2,295    2,520    2,698    3,024    3,650    3,996    4,350
Unit Selling Price                      $40.00   $40.40   $40.80   $41.21   $41.62   $42.04   $42.46   $42.89   $43.31   $43.75
Sales Growth                                      24.3%    21.2%    18.9%    10.9%     8.1%    13.2%    21.9%    10.6%    10.0%

Cost per Unit                           $20.00   $20.16   $20.32   $20.48   $20.65   $20.81   $20.98   $21.15   $21.32   $21.49
Royalties per Unit                       $0.00    $0.00    $0.00    $0.00    $0.00    $0.00    $0.00    $0.00    $0.00    $0.00
                                       -------- -------- -------- -------- -------- -------- -------- -------- -------- --------
Total Cost per Unit                     $20.00   $20.16   $20.32   $20.48   $20.65   $20.81   $20.98   $21.15   $21.32   $21.49
COGS/Sales                               50.0%    49.9%    49.8%    49.7%    49.6%    49.5%    49.4%    49.3%    49.2%    49.1%
R&D/Sales                                 6.0%     7.0%     8.0%     9.0%    10.0%    10.0%    10.0%    10.0%    10.0%    10.0%
Selling & Marketing/Sales                12.0%    12.0%    12.0%    12.0%    12.0%    12.0%    12.0%    12.0%    12.0%    12.0%
G&A/Sales                                14.0%    11.8%     9.5%     7.3%     5.0%     5.0%     5.0%     5.0%     5.0%     5.0%
Depreciation/Assets                       8.0%     8.0%     8.0%     8.0%     8.0%     8.0%     8.0%     8.0%     8.0%     8.0%
Tax Rate                                 33.0%    33.0%    33.0%    33.0%    33.0%    33.0%    33.0%    33.0%    33.0%    33.0%

EBITDA/Sales                             18.0%    19.3%    20.7%    22.1%    23.4%    23.5%    23.6%    23.7%    23.8%    23.9%
EBIT/Sales                               14.1%    15.8%    17.5%    19.1%    20.5%    20.7%    20.9%    21.2%    21.4%    21.5%

BALANCE SHEET ASSUMPTIONS
Days Receivable                          90.0     90.0     90.0     90.0     90.0     90.0     90.0     90.0     90.0     90.0
Inventory Days                          180.0    180.0    180.0    180.0    180.0    180.0    180.0    180.0    180.0    180.0
Inventory Turns                           2.0x     2.0x     2.0x     2.0x     2.0x     2.0x     2.0x     2.0x     2.0x     2.0x
A/P Accruals % of Inventory              33.0%    33.0%    33.0%    33.0%    33.0%    33.0%    33.0%    33.0%    33.0%    33.0%

Capital Expenditures                     $1.7     $4.9     $5.2     $5.4     $5.6     $3.7     $7.0     $9.5     $6.8     $8.1
Capital Expenditure as % of Net Sales     3.2%     7.5%     6.5%     5.7%     5.4%     3.3%     5.5%     6.1%     3.9%     4.2%



                                                       WASSERSTEIN PERELLA & CO.
- --------------------------------------------------------------------------------



MYCOGEN                          VALUATION: DCF ANALYSIS - BRAZIL MODEL EXAMPLE
- --------------------------------------------------------------------------------
BRAZIL NET ASSETS PROJECTIONS ($MM)



                               1998     1999     2000     2001    2002     2003     2004    2005      2006     2007
                            -------  -------   ------   ------  ------   ------  -------  ------    ------   ------
                                                                                  
NET ASSETS CALCUATION
Account Recivable              13.2     16.4     19.9     23.6    26.2     28.4     32.1     39.1     43.3     47.6
Inventories                    13.2     16.4     19.8     23.5    26.0     28.1     31.7     38.6     42.6     46.7
A/P & Accruals                 (4.4)    (5.4)    (6.5)    (7.8)   (8.6)    (9.3)   (10.5)   (12.7)   (14.1)   (15.4)
Net Working Capital           $22.0    $27.4    $33.2    $39.4   $43.7    $47.2   $ 53.4   $ 65.0   $ 71.8   $ 78.9
PP&E                           21.0     24.0     27.0     30.0    33.0     34.0     38.0     44.0     47.0     51.0
Intangible Asets                9.3      8.9      8.5      8.1     7.7      7.3      6.9      6.5      6.1      5.7

NET ASSETS                    $52.3    $60.3    $68.6    $77.5   $84.3    $88.4   $ 98.2   $115.5   $124.9   $135.5

Total Operating Income        $ 6.4    $ 6.7    $ 8.4    $11.8   $17.5    $24.2   $ 36.8   $ 64.9   $103.5   $149.7
Less: Taxes Paid               (2.1)    (2.2)    (2.8)    (3.9)   (5.8)    (8.0)   (12.1)   (21.4)   (34.2)   (49.4)
Plus: D&A                       2.1      2.3      2.6      2.8     3.0      3.1      3.4      3.9      4.2      4.5
Less: Capital Expenditure      (1.7)    (4.9)    (5.2)    (5.4)   (5.6)    (3.7)    (7.0)    (9.5)    (6.8)    (8.1)
Less: Increase in NWC         (22.0)    (5.3)    (5.8)    (6.2)   (4.3)    (3.5)    (6.2)   (11.6)    (6.8)    (7.1)

UNLEVERED FREE CASH FLOW     ($17.4)   ($3.5)   ($2.8)   ($0.9)  $ 4.9    $12.1   $ 14.9   $ 26.2    $59.9    $89.6



                                                       WASSERSTEIN PERELLA & CO.
- --------------------------------------------------------------------------------



MYCOGEN                          VALUATION: DCF ANALYSIS - BRAZIL MODEL EXAMPLE
- --------------------------------------------------------------------------------
BRAZIL CORN INCOME STATEMENT AND NET ASSETS PROJECTIONS ($MM)



                                 1998     1999     2000     2001    2002     2003     2004     2005     2006     2007
                               -------  -------   ------   ------  -------   ------  -------  ------   ------   ------
                                                                                     
Total Operating Revenue         $52.8     $65.7    $79.6    $94.6   $104.9   $113.4   $128.4  $156.5   $173.1   $190.3
  Cost of Goods Sold             26.4      32.8     39.6     47.0     52.0     56.1     63.4    77.2     85.2     93.5 
                              -------   -------  -------   ------  -------   ------  -------  ------   ------   ------
GROSS PROFIT                     26.4      32.9     39.9     47.6     52.8     57.3     65.0    79.4     87.9     96.8 

  Research & Development          3.2       4.6      6.4      8.5     10.5     11.3     12.8    15.7     17.3     19.0 
  Selling and Marketing           6.3       7.9      9.5     11.3     12.6     13.6     15.4    18.8     20.8     22.8 
  General & Administrative        7.4       7.7      7.6      6.9      5.2      5.7      6.4     7.8      8.7      9.5
                              -------   -------  -------   ------  -------   ------  -------  ------   ------   ------
                                 16.9      20.2     23.5     26.7     28.3     30.6     34.7    42.3     46.7     51.4
EBITDA                            9.5      12.7     16.5     20.9     24.5     26.7     30.3    37.1     41.1     45.4
Depreciation                      1.7       1.9      2.2      2.4      2.6      2.7      3.0     3.5      3.8      4.1
Amortization                      0.4       0.4      0.4      0.4      0.4      0.4      0.4     0.4      0.4      0.4
                              -------   -------  -------   ------  -------   ------  -------  ------   ------   ------
EBIT                              7.4      10.4     13.9     18.1     21.5     23.5     26.8    33.2     37.0     41.0
  Contract and Other Revenue        -         -        -        -        -        -        -       -        -        -
                              -------   -------  -------   ------  -------   ------  -------  ------   ------   ------
                              
TOTAL OPERATING INCOME           $7.4     $10.4    $13.9    $18.1    $21.5    $23.5    $26.8   $33.2    $37.0    $41.0
                              
NET ASSETS CALCULATION                                                                                         
Accounts Receivable              13.2      16.4     19.9     23.6     26.2     28.4     32.1    39.1     43.3     47.6  
Inventories                      13.2      16.4     19.8     23.5     26.0     28.1     31.7    38.6     42.6     46.7  
A/P & Accruals                   (4.4)     (5.4)    (6.5)    (7.8)    (8.6)    (9.3)   (10.5)  (12.7)   (14.1)   (15.4)
                              -------   -------  -------   ------  -------   ------  -------  ------   ------   ------
Net Working Capital             $22.0     $27.4    $33.2    $39.4    $43.7    $47.2    $53.4   $65.0    $71.8    $78.9
PP&E                             21.1      24.0     27.0     30.0     33.0     34.0     38.0    44.0     47.0     51.0
Intangible Assets                 9.3       8.9      8.5      8.1      7.7      7.3      6.9     6.5      6.1      5.7
                              -------   -------  -------   ------  -------   ------  -------  ------   ------   ------
                              
NET ASSETS                      $52.3     $60.3    $68.6    $77.5    $84.3    $88.4    $98.2  $115.2   $124.9   $135.5 

Total Operating Income           $7.4     $10.4    $13.9    $18.1    $21.5    $23.5    $26.8   $33.2    $37.0    $41.0 
Less: Taxes Paid                 (2.4)     (3.4)    (4.6)    (6.0)    (7.1)    (7.8)    (8.9)  (10.9)   (12.2)   (13.5) 
Plus: D&A                         2.1       2.3      2.6      2.8      3.0      3.1      3.4     3.9      4.2      4.5 
Less: Capital Expenditure        (1.7)     (4.9)    (5.2)    (5.4)    (5.6)    (3.7)    (7.0)   (9.5)    (6.8)    (8.1)
Less: Increase  in NWC          (22.0)     (5.3)    (5.8)    (6.2)    (4.3)    (3.5)    (6.2)  (11.6)    (6.8)    (7.1)
                              -------   -------  -------   ------  -------   ------  -------  ------   ------   ------
UNLEVERED FREE CASH FLOW       ($16.7)    ($1.0)    $0.9     $3.3     $7.5    $11.7     $8.2    $5.0    $15.4    $16.8


                                                       WASSERSTEIN PERELLA & CO.
- --------------------------------------------------------------------------------



MYCOGEN                         VALUATION: DCF ANALYSIS - BRAZIL MODEL EXAMPLE
- ------------------------------------------------------------------------------
BRAZIL EARLY CORN TRAIT REVENUES AND EXPENSES ($MM, EXCEPT PER UNIT PRICE AND 
UNITS IN 000S)




                                     1998    1999     2000   2001    2002    2003    2004    2005    2006    2007
                                     -----   -----   -----   -----   -----   -----   -----   -----  ------  ------
                                                                              
Corn Market Share                    1,320   1,625   1,950   2,295   2,520   2,698   3,024   3,650   3,996   4,350
HERBICIDE RESISTANCE (THIRD PARTY)
Gross Price per Hectare              $0.00   $0.00   $0.00   $0.00   $5.00   $4.80   $4.60   $4.40   $4.20   $4.00
% Market Share Penetrated              0.0%    0.0%    0.0%    0.0%    5.0%   11.0%   18.0%   24.0%   30.0%   50.0%
                                     -----   -----   -----   -----   -----   -----   -----   -----  ------  ------
    Revenue                            0.0     0.0     0.0     0.0     0.6     1.4     2.5     3.9     5.0     8.7

SPODOPTERA (MYCOGEN)
Gross Price per Hectare              $0.00   $0.00   $0.00   $0.00   $0.00  $21.00  $19.50  $18.00  $16.50  $15.00
% of Market Share Penetrated           0.0%    0.0%    0.0%    0.0%    3.0%    5.0%   11.0%   18.0%   24.0%   30.0%
                                     -----   -----   -----   -----   -----   -----   -----   -----  ------  ------
    Revenue                            0.0     0.0     0.0     0.0     0.0     2.8     6.5    11.8    15.8    19.6

ELASMOPALPOST (MYCOGEN)
Gross Price per Hectare              $0.00   $0.00   $0.00   $0.00   $0.00   $0.00  $12.00  $10.67   $9.33   $8.00
% of Market Share Penetrated           0.0%    0.0%    0.0%    0.0%    0.0%    0.0%    5.0%   13.0%   22.0%   30.0%
                                     -----   -----   -----   -----   -----   -----   -----   -----  ------  ------
    Revenue                            0.0     0.0     0.0     0.0     0.0     0.0     1.8     5.1     8.2    10.4

DIABROTICA (MYCOGEN)
Gross Price per Hectare              $0.00   $0.00   $0.00   $0.00   $0.00   $0.00   $0.00  $25.00  $24.50  $24.00
% Market Share Penetrated              0.0%    0.0%    0.0%    0.0%    0.0%    0.0%    0.0%    5.0%    8.0%   10.0%
                                     -----   -----   -----   -----   -----   -----   -----   -----  ------  ------
    Revenue                            0.0     0.0     0.0     0.0     0.0     0.0     0.0     4.6     7.8    10.4

HELICOVERPA (MYCOGEN)
Gross Price per Hectare              $0.00   $0.00   $0.00   $0.00   $0.00   $0.00   $0.00   $0.00  $24.00  $24.00
% of Market Share Penetrated           0.0%    0.0%    0.0%    0.0%    0.0%    0.0%    0.0%    0.0%    5.0%    5.0%
                                     -----   -----   -----   -----   -----   -----   -----   -----  ------  ------
    Revenue                            0.0     0.0     0.0     0.0     0.0     0.0     0.0     0.0     4.8     5.2


MYCOGEN CORN TRAIT REV.               $0.0    $0.0    $0.0    $0.0    $0.6    $4.3   $10.8   $25.3   $41.7   $54.4
Corn Trait R&D Expenses                0.6     1.3     1.7     2.3     2.1     2.3     2.3     2.5     4.2     5.4
    % of Corn Seeds Sales              1.1%    2.0%    2.2%    2.4%    2.0%    2.1%    1.8%    1.6%    2.4%    2.9%
Other R&D Expenses                     0.0     0.0     0.0     0.0     0.0     0.0     0.0     0.0     0.0     0.0
                                     -----   -----   -----   -----   -----   -----   -----   -----  ------  ------
Total R&D Expense                      0.6     1.3     1.7     2.3     2.1     2.3     2.3     2.5     4.2     5.4

    INCOME BEFORE TAX                ($0.6)  ($1.3)  ($1.7)  ($2.3)  ($1.5)   $1.9    $8.5   $22.8   $37.5   $48.9
    Tax @ 33.0%                        0.0     0.0     0.0     0.0     0.0    (0.6)   (2.8)   (7.5)  (12.4)  (16.1)
                                     -----   -----   -----   -----   -----   -----   -----   -----  ------  ------
    CASH FLOW                        ($0.6)  ($1.3)  ($1.7)  ($2.3)  ($1.5)   $1.3    $5.7   $15.3   $25.1   $32.8
    NOL Carry                         $0.2    $0.4    $0.6    $0.8    $0.5    $0.0    $0.0    $0.0    $0.0    $0.0



                                                     WASSERSTEIN PERELLA & CO.
- ------------------------------------------------------------------------------



MYCOGEN                         VALUATION: DCF ANALYSIS - BRAZIL MODEL EXAMPLE
- ------------------------------------------------------------------------------
BRAZIL SOYBEAN EARLY TRAITS REVENUES AND EXPENSES ($MM, EXCEPT PER UNIT PRICE 
AND UNITS IN 000S)




                                     1998    1999     2000   2001    2002    2003    2004    2005    2006    2007
                                     -----   -----   -----   -----   -----   -----   -----   -----  ------  ------
                                                                             

Soybean Market (Hectares)            2,500   2,550   2,601   2,653   2,706   2,760   2,815   2,872   2,929   2,988
Mycogen Market Share                  90.0%   90.0%   90.0%   90.0%   90.0%   90.0%   90.0%   90.0%   90.0%   90.0%
HERBICIDE RESISTANCE (THIRD PARTY)                                                                          
Gross Price per Hectare              $0.00   $0.00   $0.00   $0.00   $0.00   $5.00   $4.75   $4.50   $4.25   $4.00
% Market Share Penetrated              0.0%    0.0%    0.0%    0.0%    0.0%    1.0%    2.0%    3.0%    4.0%    5.0%
                                     -----   -----   -----   -----   -----   -----   -----  ------  ------  ------
    Revenue                            0.0     0.0     0.0     0.0     0.0     0.1     0.2     0.3     0.4     0.5
Bt CYST (MYCOGEN)                                                                                           
Gross Price per Hectare              $0.00   $0.00   $0.00   $0.00   $0.00   $0.00   $0.00  $12.00  $12.00  $12.00
% of Market Share Penetrated           0.0%    0.0%    0.0%    0.0%    0.0%    0.0%    0.0%    2.0%    4.0%    6.0%
                                     -----   -----   -----   -----   -----   -----   -----  ------  ------  ------
    Revenue                            0.0     0.0     0.0     0.0     0.0     0.0     0.0     0.7     1.4     2.2
                                                                                                            
MYCOGEN SOY. TRAIT REV.               $0.0    $0.0    $0.0    $0.0    $0.0    $0.1    $0.2    $1.0    $1.9    $2.7
Soy Trait R&D Expenses                 0.0     0.8     1.0     1.0     1.2     0.6     0.6     0.0     0.0     0.0
    % of Soya Seeds Sales              0.0%    0.0%    0.0%    0.0%    0.0%    0.0%    0.0%    0.0%    0.0%    0.0%
Other R&D Expenses                     0.0     0.0     0.0     0.0     0.0     0.0     0.0     0.0     0.0     0.0
                                     -----   -----   -----   -----   -----   -----   -----  ------  ------  ------
Total R&D Expense                      0.0     0.8     1.0     1.0     1.2     0.6     0.6     0.0     0.0     0.0
                                                                                                            
    INCOME BEFORE TAX                ($0.0)  ($0.8)  ($1.0)  ($1.0)  ($1.2)  ($0.5)  ($0.4)   $1.0    $1.9    $2.7
    Tax @ 33.0%                        0.0     0.0     0.0     0.0     0.0     0.0     0.0    (0.3)   (0.6)   (0.9)
                                     -----   -----   -----   -----   -----   -----   -----  ------  ------  ------
    CASH FLOW                        ($0.0)  ($0.8)  ($1.0)  ($1.0)  ($1.2)  ($0.5)  ($0.4)   $0.7    $1.2    $1.8
    NOL Carry                         $0.0    $0.3    $0.3    $0.3    $0.4    $0.2    $0.1    $0.0    $0.0    $0.0
                                                                                                            
  TOTAL EARLY TRAIT CF               ($0.6)  ($2.1)  ($2.7)  ($3.3)  ($2.7)   $0.8    $5.3   $16.0   $26.4   $34.6
                                                                                                            

                                                                              
                                                     WASSERSTEIN PERELLA & CO.
- ------------------------------------------------------------------------------



MYCOGEN                        VALUATION : DCF ANALYSIS - BRAZIL MODEL EXAMPLE
- ------------------------------------------------------------------------------
BRAZIL OUTPUT TRAITS REVENUES AND EXPENSES ($MM, EXCEPT PER UNIT PRICE AND 
UNITS IN 000S)






                                  1998     1999     2000     2001     2002     2003      2004     2005      2006      2007
                                 ------   ------   ------   -------  ------   ------    -------  -------   -------   -------
                                                                                            
Corn Market Share                 1,320    1,625    1,950    2,295     2,520    2,698     3,024    3,650     3,996     4,350
HIGH OIL/NUTRISEED'
Gross Price per Hectare           $0.00    $0.00    $4.80    $4.80     $4.80    $4.80    $ 4.80   $ 4.80    $ 4.80    $ 4.80
% Market Share Penetrated          0.0 %    0.0 %    0.0 %    0.0 %     5.0 %   11.0 %    18.0 %   24.0 %    30.0 %    50.0 %
                                 ------   ------   ------   -------  ------   ------    -------  -------   -------   -------
    Revenue                        0.0      0.0      0.0      0.0       0.6      1.4       2.6      4.2       5.8      10.4
HIGH OLEIC
Gross Price per Hectare           $0.00    $0.00    $0.00    $0.00     $0.00    $0.00    $ 9.60   $ 9.60    $ 9.60    $ 9.60
% of Market Share Penetrated       0.0 %    0.0 %    0.0 %    0.0 %     0.0 %    0.0 %     1.0 %    4.0 %     8.0 %    10.0 %
                                 ------   ------   ------   -------  ------   ------    -------  -------   -------   -------
    Revenue                        0.0      0.0      0.0      0.0       0.0      0.0       0.3      1.4       3.1       4.2
LOW PHYTATE
Gross Price per Hectare           $0.00    $0.00    $0.00    $0.00     $0.00    $0.00    $19.20   $19.20    $14.40    $12.00
% Market Share Penetrated          0.0 %    0.0 %    0.0 %    0.0 %     0.0 %    1.0 %     3.0 %    6.0 %     9.0 %    12.0 %
                                 ------   ------   ------   -------  ------   ------    -------  -------   -------   -------
    Revenue                        0.0      0.0      0.0      0.0       0.0      0.5       1.7      3.2       5.2       6.3
FORAGE PROTEIN MODIFICATION
Gross Price per Hectare            $0.00    $0.00    $0.00    $0.00     $0.00    $0.00    $0.00   $ 0.00    $ 0.00    $36.00
% of Market Share Penetrated        0.0 %    0.0 %    0.0 %    0.0 %     0.0 %    0.0 %    0.0 %    0.0 %     0.0 %     2.0 % 
                                 ------   ------   ------   -------  ------   ------    -------  -------   -------   -------
    Revenue                         0.0      0.0      0.0      0.0       0.0      0.0      0.0      0.0       0.0       3.1
GREEN GENE- INCREASED BIOMASS
Gross Price per Hectare            $0.00    $0.00    $0.00    $0.00     $0.00    $0.00    $0.00   $ 0.00    $24.00    $24.00
% of Market Share Penetrated        0.0 %    0.0 %    0.0 %    0.0 %     0.0 %    0.0 %    0.0 %    0.0 %     3.0 %    10.0 %
                                 ------   ------   ------   -------  ------   ------    -------  -------   -------   -------
    Revenue                         0.0      0.0      0.0      0.0       0.0      0.0      0.0      0.0       2.9      10.4
Soybean Market                     1,320    1,625    1,950    2,295     2,520    2,698     3,024    3,650     3,996    4,350
F.MT/Mycogen Share                 90.0 %   90.0 %   90.0 %   90.0 %    90.0 %   90.0 %    90.0 %  90.0 %    90.0 %    90.0 %
HIGH NUTRITION PROTEIN (DEMETER)
Gross Price per Hectare            $0.00    $0.00    $0.00    $0.00     $0.00    $0.00    $0.00   $ 0.00    $72.00    $72.00
% Market Share Penetrated           0.0 %    0.0 %    0.0 %    0.0 %     0.0 %    0.0 %    0.0 %    0.0 %     5.0 %    10.0 %
                                 ------   ------   ------   -------  ------   ------    -------  -------   -------   -------
    Revenue                         0.0      0.0      0.0      0.0       0.0      0.0      0.0      0.0      14.4      31.3
MYCOGEN TRAIT REV.                 $0.0     $0.0     $0.0     $0.0      $0.6     $1.9     $4.6    $ 8.8     $31.3     $65.8
Corn Output R&D                     0.4      1.0      1.7      2.2       1.5      1.5      1.7      0.9       3.1       6.6
    % of Seeds Sales                0.8 %    1.5 %    2.1 %    2.3 %     1.4 %    1.3 %    1.3 %    0.6 %     1.8 %      3.5 %
Soybean R&D                         0.0      0.4      0.6      0.4       0.2      0.6      0.6      0.0       1.2        2.5

    INCOME BEFORE TAX             ($0.4)   ($1.4)   ($2.3)   ($2.6)    ($1.1)   ($0.2)    $2.4     $7.9     $27.0      $56.7
    Tax @ 33.0%                     0.0      0.0      0.0      0.0       0.0      0.0     (0.8)    (2.6)     (8.9)     (18.7)
                                 ------   ------   ------   -------  ------   ------    -------  -------   -------   -------
    CASH FLOW                     ($0.4)   ($1.4)   ($2.3)   ($2.6)    ($1.1)   ($0.2)    $1.6     $5.3     $18.8      $38.0
    NOL Carry                      $0.1     $0.5     $0.8     $0.9      $0.4     $0.1     $0.0    $ 0.0     $ 0.0      $ 0.0
Corn Output CF                    ($0.4)   ($1.4)   ($2.3)   ($2.6)    ($1.1)   ($0.2)    $1.6    $ 5.3     $ 8.4      $17.0
Soybean Output CF                 $ 0.0    ($0.4)   ($0.6    ($0.4)    ($0.2)   ($0.6)   ($0.6)   $ 0.0     $ 8.9      $19.3




MYCOGEN                        VALUATION : DCF ANALYSIS - BRAZIL MODEL EXAMPLE
- ------------------------------------------------------------------------------
BRAZIL OUTPUT TRAITS REVENUES AND EXPENSES ($MM, EXCEPT PER UNIT PRICE AND 
UNITS IN 000S)






                                  1998     1999     2000     2001     2002     2003      2004     2005      2006      2007
                                 ------   ------   ------   -------  ------   ------    -------  -------   -------   -------
                                                                                            

Corn Market Share                  392      461       536      617      703      710       718     725        733        740
MOLD MYCOTOXIN
Gross Price per Hectare           $0.00    $0.00    $0.00    $0.00     $0.00    $0.00     $0.00    $0.00    $12.00    $12.00
% Market Share Penetrated          0.0 %    0.0 %    0.0 %    0.0 %     0.0 %    0.0 %    0.0 %    0.0 %      0.2 %     5.0 %
                                 ------   ------   ------   -------  ------   ------    -------  -------   -------   -------
    Revenue                        0.0      0.0      0.0      0.0       0.0      0.0      0.0      0.0        0.2       0.4

Brazil Soyabean Market           2,500     2,500    2,601    2,653    2,706    2,760     2,815    2,872      2,929     2,988
F.MT/Mycogen Share               90.0 %   90.0 %   90.0 %   90.0 %    90.0 %   90.0 %    90.0 %   90.0 %     90.0 %    90.0 %
SOYBEAN DISEASE I  
Gross Price per Hectare          $0.00    $0.00    $0.00    $0.00     $0.00    $0.00     $0.00    $0.00      $0.00     $0.00
% of Market Share Penetrated      0.0 %    0.0 %    0.0 %    0.0 %     0.0 %   10.0 %    20.0 %   30.0 %     40.0 %    50.0 %
                                 ------   ------   ------   -------  ------   ------    -------  -------   -------   -------
    Revenue                       0.0      0.0      0.0      0.0       0.0      0.0       0.0      0.0        0.0       0.0

CORN TRAIT REVENUE               $0.0     $0.0     $0.0     $0.0      $0.0     $0.0      $0.0     $0.0       $0.2      $0.4 
SOYABEAN TRAIT REVENUE            0.0      0.0      0.0      0.0       0.0      0.0       0.0      0.0        0.0       0.0
                                 ------   ------   ------   -------  ------   ------    -------  -------   -------   -------
MYCOGEN DISEASE TRAIT TRAIT REV. $0.0     $0.0     $0.0     $0.0      $0.0     $0.0      $0.0     $0.0       $0.2      $0.4 

Corn Trait R&D Expenses           0.0      0.0      0.0      0.0       0.0      0.6       0.6      0.0        0.0       0.0
    % of Corn Seeds Sales         0.0 %    0.0 %    0.0 %    0.0 %     0.0 %    0.5 %     0.5 %    0.0 %      0.2 %     5.0 %
Soyabean Trait R&D Expenses       0.0      0.0      0.0      0.0       0.0      0.0       0.0      0.0        0.0       0.0
                                 ------   ------   ------   -------  ------   ------    -------  -------   -------   -------
R&D Expense (with Alloc.)         0.0      0.2      0.5      0.3       0.2      0.6       0.6      0.0        0.0       0.0

    INCOME BEFORE TAX            $0.0    ($0.2)   ($0.5)   ($0.3)    ($0.2)   ($0.6)    ($0.6)    $0.0       $0.2      $0.4
    Tax @ 33.0%                   0.0      0.0      0.0      0.0       0.0      0.0       0.0      0.0       (0.1)     (0.1)
                                 ------   ------   ------   -------  ------   ------    -------  -------   -------   -------
    CASH FLOW                    $0.0    ($0.2)   ($0.5)   ($0.3)    ($0.2)   ($0.6)    ($0.6)    $0.0       $0.2      $0.5
    NOL Carry                    $0.0     $0.1     $0.2     $0.1      $0.1     $0.2      $0.2     $0.0       $0.0      $0.0 




MYCOGEN                          VALUATION: DCF ANALYSIS - BRAZIL MODEL EXAMPLE
- -------------------------------------------------------------------------------
BRAZIL CORN DISCOUNTED CASH FLOW ANALYSIS



- ------------------                                 ----------------------------------------------------------
  DISCOUNT RATE                                         TERMINAL MULTIPLE OF YEAR 2007 OPERATING INCOME
- ------------------                                 -----------------------------------------------------------
                                                                               
                                                          6.0x          8.0x         10.0x          12.0x
                                                    -----------   -----------   -----------   -----------
              11.0%  PV of Free Cash Flow                $15.7         $15.7         $15.7         $15.7
                     PV of Terminal Multiple              86.6         115.4         144.3         173.1
                                                    -----------   -----------   -----------   -----------
                     Enterprise Value                   $102.3        $131.2        $160.0        $188.9
                     Less: Net Debt                        0.0           0.0           0.0           0.0
                                                    -----------   -----------   -----------   -----------
                     EQUITY VALUE                       $102.3        $131.2        $160.0        $188.9
                     IMPLIED PERPETUITY GROWTH            3.9%          5.6%          6.6%          7.3%
                       % VALUE FROM TERMINAL MULT.       84.6%         88.0%         90.2%         91.7%


              16.0%  PV of Free Cash Flow                 $7.9          $7.9          $7.9          $7.9
                     PV of Terminal Multiple              55.7          74.3          92.9         111.4
                                                    -----------   -----------   -----------   -----------
                     Enterprise Value                    $63.7         $82.2        $100.8        $119.4
                     Less: Net Debt                        0.0           0.0           0.0           0.0
                                                    -----------   -----------   -----------   -----------
                     EQUITY VALUE                        $63.7         $82.2        $100.8        $119.4
                     IMPLIED PERPETUITY GROWTH            8.6%         10.4%         11.4%         12.2%
                       % VALUE FROM TERMINAL MULT.       87.5%         90.3%         92.1%         93.4%


              21.0%  PV of Free Cash Flow                 $2.7          $2.7          $2.7          $2.7
                     PV of Terminal Multiple              36.5          48.7          60.9          73.1
                                                    -----------   -----------   -----------   -----------
                     Enterprise Value                    $39.3         $51.4         $63.6         $75.8
                     Less: Net Debt                        0.0           0.0           0.0           0.0
                                                    -----------   -----------   -----------   -----------
                     EQUITY VALUE                        $39.3         $51.4         $63.6         $75.8
                     IMPLIED PERPETUITY GROWTH           13.3%         15.1%         16.2%         17.0%
                       % VALUE FROM TERMINAL MULT.       93.1%         94.7%         95.7%         96.4%




                   -------------------------------------------------------------

                      SELECTED EQUITY VALUE RANGE  $39        -         $189

                   -------------------------------------------------------------



                                                       WASSERSTEIN PERELLA & CO.
- --------------------------------------------------------------------------------




MYCOGEN                          VALUATION: DCF ANALYSIS - BRAZIL MODEL EXAMPLE
- -------------------------------------------------------------------------------
BRAZIL EARLY TRAIT DISCOUNTED CASH FLOW ANALYSIS



- ------------------                                 -----------------------------------------------------------
  DISCOUNT RATE                                         YEAR 2007 CASH FLOW GROWTH RATE
- ------------------                                 -----------------------------------------------------------
                                                                               
                                                          8.0%         10.0%         12.0%          14.0%
                                                    -----------   -----------   -----------   -----------
              20.0%  PV of Free Cash Flow                 $9.9          $9.9          $9.9          $9.9
                     PV of Terminal Multiple              50.3          61.5          78.2         106.1
                                                    -----------   -----------   -----------   -----------
                     Enterprise Value                    $60.2         $71.4         $88.1        $116.1
                     Less: Net Debt                        0.0           0.0           0.0           0.0
                                                    -----------   -----------   -----------   -----------
                     EQUITY VALUE                        $60.2         $71.4         $88.1        $116.1
                     IMPLIED PERPETUITY GROWTH            8.0%         10.0%         12.0%         14.0%
                       % VALUE FROM TERMINAL MULT.       83.5%         86.1%         88.7%         91.5%


              25.0%  PV of Free Cash Flow                 $5.8          $5.8          $5.8          $5.8
                     PV of Terminal Multiple              23.6          27.2          32.0          38.5
                                                    -----------   -----------   -----------   -----------
                     Enterprise Value                    $29.4         $33.0         $37.8         $44.3
                     Less: Net Debt                        0.0           0.0           0.0           0.0
                                                    -----------   -----------   -----------   -----------
                     EQUITY VALUE                        $29.4         $33.0         $37.8         $44.3
                     IMPLIED PERPETUITY GROWTH            8.0%         10.0%         12.0%         14.0%
                       % VALUE FROM TERMINAL MULT.       80.4%         82.5%         84.7%         87.0%


              30.0%  PV of Free Cash Flow                 $3.1          $3.1          $3.1          $3.1
                     PV of Terminal Multiple              12.3          13.8          15.6          17.9
                                                    -----------   -----------   -----------   -----------
                     Enterprise Value                    $15.4         $16.9         $18.7         $21.0
                     Less: Net Debt                        0.0           0.0           0.0           0.0
                                                    -----------   -----------   -----------   -----------
                     EQUITY VALUE                        $15.4         $16.9         $18.7         $21.0
                     IMPLIED PERPETUITY GROWTH            8.0%         10.0%         12.0%         14.0%
                       % VALUE FROM TERMINAL MULT.       79.9%         81.6%         83.4%         85.2%



                   -------------------------------------------------------------

                       SELECTED EQUITY VALUE RANGE  $15        -         $116

                   -------------------------------------------------------------





                                                       WASSERSTEIN PERELLA & CO.
- --------------------------------------------------------------------------------



MYCOGEN                          VALUATION: DCF ANALYSIS - BRAZIL MODEL EXAMPLE
- -------------------------------------------------------------------------------
BRAZIL OUTPUT TRAITS DISCOUNTED CASH FLOW ANALYSIS




- ------------------                                   ------------------------------------------------
DISCOUNT RATE                                                  YEAR 2007 CASH FLOW GROWTH RATE
- ------------------                                   ------------------------------------------------
                                                             1.0%        1.5%       2.0%       2.5%
                                                         --------    --------   --------   --------
                                                                            
              25.0%   PV of Free Cash Flow                   $3.9        $3.9       $3.9       $3.9
                      PV of Terminal Multiple                17.2        17.6       18.1       18.6
                                                         --------    --------   --------   --------
                      Enterprise Value                      $21.0       $21.5      $21.9      $22.4
                      Less: Net Debt                          0.0         0.0        0.0        0.0
                                                         --------    --------   --------   --------
                      EQUITY VALUE                          $21.0       $21.5      $21.9      $22.4
                      IMPLIED PERPETUITY GROWTH              1.0%        1.5%       2.0%       2.5%
                        % VALUE FROM TERMINAL MULT.         81.7%       82.0%      82.4%      82.8%


              35.0%   PV of Free Cash Flow                   $0.7        $0.7       $0.7       $0.7
                      PV of Terminal Multiple                 5.6         5.7        5.8        6.0
                                                         --------    --------   --------   --------
                      Enterprise Value                       $6.3        $6.4       $6.6       $6.7
                      Less: Net Debt                          0.0         0.0        0.0        0.0
                                                         --------    --------   --------   --------
                      EQUITY VALUE                           $6.3        $6.4       $6.6       $6.7
                      IMPLIED PERPETUITY GROWTH              1.0%        1.5%       2.0%       2.5%
                        % VALUE FROM TERMINAL MULT.         88.7%       88.9%      89.1%      89.3%


              45.0%   PV of Free Cash Flow                  ($0.5)      ($0.5)     ($0.5)     ($0.5)
                      PV of Terminal Multiple                 2.1         2.2        2.2        2.2
                                                         --------    --------   --------   --------
                      Enterprise Value                       $1.6        $1.6       $1.7       $1.7
                      Less: Net Debt                          0.0         0.0        0.0        0.0
                                                         --------    --------   --------   --------
                      EQUITY VALUE                           $1.6        $1.6       $1.7       $1.7
                      IMPLIED PERPETUITY GROWTH              1.0%        1.5%       2.0%       2.5%
                        % VALUE FROM TERMINAL MULT.        133.0%      132.3%     131.6%     131.0%




                                ------------------------------------------------

                                  SELECTED EQUITY VALUE RANGE   $2     -    $22

                                ------------------------------------------------




                                                      WASSERSTEIN PERELLA & CO.
- -------------------------------------------------------------------------------



MYCOGEN                          VALUATION: DCF ANALYSIS - BRAZIL MODEL EXAMPLE
- -------------------------------------------------------------------------------
BRAZIL DISEASE RESISTANCE DISCOUNTED CASH FLOW ANALYSIS




- ------------------                                   ------------------------------------------------
DISCOUNT RATE                                                  YEAR 2007 CASH FLOW GROWTH RATE
- ------------------                                   ------------------------------------------------
                                                            25.0%       27.0%      29.0%      31.0%
                                                         --------    --------   --------   --------
                                                                            
              40.0%   PV of Free Cash Flow                  ($0.5)      ($0.5)     ($0.5)     ($0.5)
                      PV of Terminal Multiple                 0.2         0.2        0.2        0.3
                                                         --------    --------   --------   --------
                      Enterprise Value                      ($0.4)      ($0.3)     ($0.3)     ($0.2)
                      Less: Net-Debt                          0.0         0.0        0.0        0.0
                                                         --------    --------   --------   --------
                      EQUITY VALUE                          ($0.4)      ($0.3)     ($0.3)     ($0.2)
                      IMPLIED PERPETUITY GROWTH             25.0%       27.0%      29.0%      31.0%
                        % VALUE FROM TERMINAL MULT.        --          --         --         --
                                                       
              50.0%   PV of Free Cash Flow                  ($0.4)      ($0.4)     ($0.4)     ($0.4)
                      PV of Terminal Multiple                 0.0         0.0        0.0        0.0  
                                                         --------    --------   --------   --------  
                      Enterprise Value                      ($0.4)      ($0.4)     ($0.4)     ($0.4) 
                      Less: Net Debt                          0.0         0.0        0.0        0.0  
                                                         --------    --------   --------   --------  
                      EQUITY VALUE                          ($0.4)      ($0.4)     ($0.4)     ($0.4) 
                      IMPLIED PERPETUITY GROWTH           (100.0%)    (100.0%)   (100.0%)   (100.0%)
                        % VALUE FROM TERMINAL MULT.      0.0%        0.0%       0.0%       0.0%     
                                                       
                                                       
              60.0%   PV of Free Cash Flow                  ($0.3)      ($0.3)     ($0.3)     ($0.3) 
                      PV of Terminal Multiple                 0.0         0.0        0.0        0.0  
                                                         --------    --------   --------   --------  
                      Enterprise Value                      ($0.3)      ($0.3)     ($0.3)     ($0.3) 
                      Less: Net Debt                          0.0         0.0        0.0        0.0  
                                                         --------    --------   --------   --------  
                      EQUITY VALUE                          ($0.3)      ($0.3)     ($0.3)     ($0.3) 
                      IMPLIED PERPETUITY GROWTH           (100.0%)    (100.0%)   (100.0%)   (100.0%) 
                        % VALUE FROM TERMINAL MULT.      0.0%        0.0%       0.0%       0.0%      



                                ------------------------------------------------

                                  SELECTED EQUITY VALUE RANGE   ($0)    -   ($0)

                                ------------------------------------------------




                                                      WASSERSTEIN PERELLA & CO.
- -------------------------------------------------------------------------------



MYCOGEN                           VALUATION: DCF ANALYSIS - BRAZIL MODEL EXAMPLE
- --------------------------------------------------------------------------------
BRAZIL CORN EARLY TRAITS DISCOUNTED CASH FLOW ANALYSIS


DISCOUNT RATE                                  YEAR 2007 CASH FLOW GROWTH RATE
- ----------------                          ----------------------------------------
                                                               
                                             8.0%       10.0%      12.0%     14.0%
                                          --------   --------    -------   -------
    20.0% PV of Free Cash Flow               $11.6      $11.6      $11.6    $ 11.6
          PV of Terminal Multiple             47.7       58.2       74.1     100.6
                                          --------   --------    -------   -------
          Enterprise Value                   $59.3      $69.9      $85.8    $112.2
          Less: Net Debt                       0.0        0.0        0.0       0.0
                                          --------   --------    -------   -------
          EQUITY VALUE                       $59.3      $69.9      $85.8    $112.2
          IMPLIED PERPETUITY GROWTH           8.0%      10.0%      12.0%     14.0%
            % VALUE FROM TERMINAL MULT.      80.4%      83.4%      86.4%     89.6%
                                                                           
                                                                           
    25.0% PV of Free Cash Flow                $7.4       $7.4      $ 7.4    $  7.4
          PV of Terminal Multiple             22.4       25.8       30.3      36.5
                                          --------   --------    -------   -------
          Enterprise Value                   $29.7      $33.2      $37.7    $ 43.8
          Less: Net Debt                       0.0        0.0        0.0       0.0
                                          --------   --------    -------   -------
          EQUITY VALUE                       $29.7      $33.2      $37.7    $ 43.8
          IMPLIED PERPETUITY GROWTH           8.0%      10.0%      12.0%     14.0%
            % VALUE FROM TERMINAL MULT.      75.2%      77.8%      80.5%     83.2%
                                                                           
                                                                           
    30.0% PV of Free Cash Flow               $ 4.6      $ 4.6      $ 4.6    $  4.6
          PV of Terminal Multiple             11.7       13.1       14.8      16.9
                                          --------   --------    -------   -------
          Enterprise Value                   $16.2      $17.7      $19.4    $ 21.5
          Less: Net Debt                       0.0        0.0        0.0       0.0
                                          --------   --------    -------   -------
          EQUITY VALUE                       $16.2      $17.7      $19.4    $ 21.5
          IMPLIED PERPETUITY GROWTH           8.0%      10.0%      12.0%     14.0%
            % VALUE FROM TERMINAL MULT.      71.9%      74.1%      76.4%     78.8%


                 -------------------------------------------------------

                  SELECTED EQUITY VALUE RANGE $16      -           $112

                 -------------------------------------------------------

                                                      WASSERSTEIN PERELLA  & CO.
- --------------------------------------------------------------------------------


MYCOGEN                           VALUATION: DCF ANALYSIS - BRAZIL MODEL EXAMPLE
- --------------------------------------------------------------------------------
BRAZIL SOY BEAN EARLY TRAITS DISCOUNTED CASH FLOW ANALYSIS


DISCOUNT RATE                                    YEAR 2007 CASH FLOW GROWTH RATE
- ----------------                           -------------------------------------------
                                                                  
                                              8.0%      10.0%        12.0%      14.0%
                                           --------   --------      -------    -------
    25.0% PV of Free Cash Flow               ($1.6)     ($1.6)       ($1.6)     ($1.6)
          PV of Terminal Multiple              1.2        1.4          1.7        2.0
                                           --------   --------      -------    -------
          Enterprise Value                   ($0.4)     ($0.2)        $0.1       $0.4
          Less: Net Debt                       0.0        0.0          0.0        0.0
                                           --------   --------      -------    -------
          EQUITY VALUE                       ($0.4)     ($0.2)        $0.1       $0.4
          IMPLIED PERPETUITY GROWTH           8.0%      10.0%        12.0%      14.0%
            % VALUE FROM TERMINAL MULT.    (335.6%)   (803.6%)    2,331.4%     489.4%
                                                                               
                                                                               
    35.0% PV of Free Cash Flow               ($1.3)     ($1.3)       ($1.3)     ($1.3)
          PV of Terminal Multiple              0.4        0.4          0.4        0.5
                                           --------   --------      -------    -------
          Enterprise Value                   ($1.0)     ($0.9)       ($0.9)     ($0.9)
          Less: Net Debt                       0.0        0.0          0.0        0.0
                                           --------   --------      -------    -------
          EQUITY VALUE                       ($1.0)     ($0.9)       ($0.9)     ($0.9)
          IMPLIED PERPETUITY GROWTH           8.0%      10.0%        12.0%      14.0%
            % VALUE FROM TERMINAL MULT.     (36.5%)    (41.7%)      (48.3%)    (57.0%)
                                                                               
                                                                               
    45.0% PV of Free Cash Flow               ($1.1)     ($1.1)       ($1.1)     ($1.1)
          PV of Terminal Multiple              0.1        0.1          0.1        0.2
                                           --------   --------      -------    -------
          Enterprise Value                   ($1.0)     ($1.0)       ($1.0)     ($0.9)
          Less: Net Debt                       0.0        0.0          0.0        0.0
                                           --------   --------      -------    -------
          EQUITY VALUE                       ($1.0)     ($1.0)       ($1.0)     ($0.9)
          IMPLIED PERPETUITY GROWTH           8.0%      10.0%        12.0%      14.0%
            % VALUE FROM TERMINAL MULT.     (13.0%)    (14.2%)      (15.5%)    (17.0%)


                 -------------------------------------------------------

                  SELECTED EQUITY VALUE RANGE  ($1)      -           $0

                 -------------------------------------------------------

                                                      WASSERSTEIN PERELLA  & CO.
- --------------------------------------------------------------------------------



MYCOGEN                           VALUATION: DCF ANALYSIS - BRAZIL MODEL EXAMPLE
- --------------------------------------------------------------------------------
BRAZIL CORN OUTPUT TRAITS DISCOUNTED CASH-FLOW ANALYSIS




- ------------------                                   ------------------------------------------------
  DISCOUNT RATE                                                YEAR 2007 CASH FLOW GROWTH RATE
- ------------------                                   ------------------------------------------------
                                                             1.0%        1.5%       2.0%       2.5%
                                                         --------    --------   --------   --------
                                                                             
              25.0%   PV of Free Cash Flow                   $0.3        $0.3       $0.3       $0.3
                      PV of Terminal Multiple                 7.7         7.9        8.1        8.3
                                                         --------    --------   --------   --------
                      Enterprise Value                       $8.0        $8.2       $8.4       $8.6
                      Less: Net-Debt                          0.0         0.0        0.0        0.0
                                                         --------    --------   --------   --------
                      EQUITY VALUE                           $8.0        $8.2       $8.4       $8.6
                      IMPLIED PERPETUITY GROWTH              1.0%        1.5%       2.0%       2.5%
                        % VALUE FROM TERMINAL MULT.         96.2%       96.2%      96.3%      96.4%
                                                      
                                                      
              35.0%   PV of Free Cash Flow                 ($1.0)      ($1.0)     ($1.0)     ($1.0)
                      PV of Terminal Multiple                2.5         2.6        2.6        2.7
                                                         --------    --------   --------   --------
                      Enterprise Value                      $1.5        $1.6       $1.6       $1.7
                      Less: Net Debt                         0.0         0.0        0.0        0.0
                                                         --------    --------   --------   --------
                      EQUITY VALUE                          $1.5        $1.6       $1.6       $1.7
                      IMPLIED PERPETUITY GROWTH            1.0%        1.5%       2.0%       2.5%
                        % VALUE FROM TERMINAL MULT.      163.5%      161.4%     159.5%     157.6%
                                                      
                                                      
              45.0%   PV of Free Cash Flow                  ($1.4)      ($1.4)     ($1.4)     ($1.4)
                      PV of Terminal Multiple                 0.9         1.0        1.0        1.0
                                                         --------    --------   --------   --------
                      Enterprise Value                      ($0.4)      ($0.4)     ($0.4)     ($0.4)
                      Less: Net Debt                          0.0         0.0        0.0        0.0
                                                         --------    --------   --------   --------
                      EQUITY VALUE                          ($0.4)      ($0.4)     ($0.4)     ($0.4)
                      IMPLIED PERPETUITY GROWTH              1.0%        1.5%       2.0%       2.5%
                        % VALUE FROM TERMINAL MULT.       (221.7%)    (234.0%)   (247.5%)   (262.5%)





                                ------------------------------------------------

                                  SELECTED EQUITY VALUE RANGE   ($0)  -   $9

                                ------------------------------------------------




                                                      WASSERSTEIN PERELLA & CO.
- -------------------------------------------------------------------------------



MYCOGEN                           VALUATION: DCF ANALYSIS - BRAZIL MODEL EXAMPLE
- --------------------------------------------------------------------------------
BRAZIL SOYBEAN OUTPUT TRAITS DISCOUNTED CASH FLOW ANALYSIS








- ------------------                                   ------------------------------------------------
  DISCOUNT RATE                                                YEAR 2007 CASH FLOW GROWTH RATE
- ------------------                                   ------------------------------------------------
                                                            1.0%       1.5%       2.0%       2.5%
                                                         --------    --------   --------   --------
                                                                             
              25.0%   PV of Free Cash Flow                   $2.2        $2.2       $2.2       $2.2
                      PV of Terminal Multiple                 8.7         9.0        9.2       21.5  #
                                                         --------    --------   --------   --------  
                      Enterprise Value                      $10.9       $11.1      $11.4      $23.7
                      Less: Net-Debt                          0.0         0.0        0.0        0.0
                                                         --------    --------   --------   --------  
                      EQUITY VALUE                          $10.9       $11.1      $11.4      $23.7
                      IMPLIED PERPETUITY GROWTH              1.0%        1.5%       2.0%      14.0%
                        % VALUE FROM TERMINAL MULT.         80.0%       80.5%      80.9%      90.8%
                                                     
                                                     
              35.0%   PV of Free Cash Flow                   $0.7        $0.7       $0.7       $0.7
                      PV of Terminal Multiple                 2.9         2.9        3.0        5.2
                                                         --------    --------   --------   --------  
                      Enterprise Value                       $3.6        $3.7       $3.7       $6.0
                      Less: Net Debt                          0.0         0.0        0.0        0.0
                                                         --------    --------   --------   --------  
                      EQUITY VALUE                           $3.6        $3.7       $3.7       $6.0
                      IMPLIED PERPETUITY GROWTH              1.0%        1.5%       2.0%      14.0%
                        % VALUE FROM TERMINAL MULT.         79.2%       79.6%      79.9%      87.5%
                                                     
                                                     
              45.0%   PV of Free Cash Flow                   $0.2        $0.2       $0.2       $0.2
                      PV of Terminal Multiple                 1.1         1.1        1.1        1.7
                                                         --------    --------   --------   --------  
                      Enterprise Value                       $1.2        $1.3       $1.3       $1.9
                      Less: Net Debt                          0.0         0.0        0.0        0.0
                                                         --------    --------   --------   --------
                      EQUITY VALUE                           $1.2        $1.3       $1.3       $1.9
                      IMPLIED PERPETUITY GROWTH              1.0%        1.5%       2.0%      14.0%
                        % VALUE FROM TERMINAL MULT.         87.1%       87.3%      87.5%      91.5%



                                ------------------------------------------------

                                  SELECTED EQUITY VALUE RANGE    $1   -    $24

                                ------------------------------------------------



                                                      WASSERSTEIN PERELLA & CO.
- -------------------------------------------------------------------------------



MYCOGEN                                     VALUATION: SUMMARY OF BUSINESS UNITS
- --------------------------------------------------------------------------------
ELEMENTS OF PROJECTED BUSINESS VALUATION




BUSINESS                 CROP             TRAIT                      GEOGRAPHICAL REGION
- --------                 ----             -----                      -------------------
                                                     N. AMERICA      ARGENTINA      BRAZIL       OTHER
- ----------------------------------------------------------------------------------------------------------
                                                                              
Biopesticides              --               --             X

SoilServ                   --               --             X

Conventional Seed
                       Corn                 --             X            X             X
                       Soybeans             --             X
                       Sunflower            --             X
                       Sorghum              --             X
                       Alfalfa              --             X

Early Traits (Herbicide Resistance)

                       Corn           RR/LL                X            X             X
                       Sunflower      RR/LL                             X
                       Soybean        LL                   X
                       Sorghum        RR/LL                X

Early Traits (Insect Resistance)

                       Corn           Bt176                X
                       Corn           Spodoptera                                       X
                       Corn           Elasmopalpost                                    X
                       Corn           Diabrotica                                       X
                       Corn           Helicoverpa                                      X
                       Corn           Armyworm
                       Corn           ECB/Glufosinate      X            X
                       Corn           CRW/Glufosinate      X            X
                       Sunflower      Looper                            X
                       Sunflower      Head Moth            X
                       Sunflower      Seed Weevil          X
                       Soybean        Cyst                 X                           X





                                                       WASSERSTEIN PERELLA & CO.
- --------------------------------------------------------------------------------



MYCOGEN                                     VALUATION: SUMMARY OF BUSINESS UNITS
- --------------------------------------------------------------------------------
ELEMENTS OF PROJECTED BUSINESS VALUATION (CONT'D)




BUSINESS                 CROP             TRAIT                      GEOGRAPHICAL REGION
- --------                 ----             -----                      -------------------
                                                          N. AMERICA      ARGENTINA      BRAZIL       OTHER
- -------------------------------------------------------------------------------------------------------------
                                                                                   
                       Sorghum        Midge
                                      Greenbug Aphid
                       Alfalfa        Weevil
                                      Lepidoptera
Output                 Corn           High Oil                  X            X              X
                                      High Oil/Evt. 176         X
                                      Hi Oleic                  X            X              X
                                      Low Phytate               X            X              X
                                      Forage Protein            X            X              X
                                      Green Gene                X            X              X
                       Soyabean       High Nutrition            X                           X
                       Sunflower      High Oleic                X
                                      High Palmitic             X
                                      Quality Protein           X            X
                       Sorghum        Nutritional               X
Disease Resistance
                       Corn           Mold/Mycotoxin                         X              X
                       Sunflower      Sclerotinia               X            X
                                      Verticilian                            X


                                                       WASSERSTEIN PERELLA & CO.
- --------------------------------------------------------------------------------



MYCOGEN                                     VALUATION: SUMMARY OF BUSINESS UNITS
- --------------------------------------------------------------------------------
ELEMENTS OF PROJECTED BUSINESS VALUATION (CONT'D)



- ----------------------------------------------------------------------------------------------------------
BUSINESS                 CROP             TRAIT                      GEOGRAPHICAL REGION
                                                     N. AMERICA      ARGENTINA      BRAZIL       OTHER
- ----------------------------------------------------------------------------------------------------------
                                                                             
JV/Partner Royalties   VMO            Conventional                                               Europe
                                      Early Traits                                               Europe
                                      Output Traits                                              Europe
                       Cotton         Conventional         X            X
                                      Bud/Bollworm         X            X                        Australia
                                      Boll Weevil          X            X                           and
                                      Lygus                X                                       Greece
                       Oilseed/Humko       --              X            X
                       Oilseed/DAS         --              X
                       Rice           Stem Borer                                                 Japan
                                      Plant Hopper                                               Japan
                       Turf           White Grub           X
                                      Army/Cutworm         X
                                      Webworm              X
- ----------------------------------------------------------------------------------------------------------


                                                       WASSERSTEIN PERELLA & CO.
- --------------------------------------------------------------------------------



MYCOGEN CORPORATION                                     
- -------------------------------------------------------------------------------
SUMMARY OF VALUATION



- ---------------------------------------------------------------------------------------------------------------------
BUSINESS            CROP       REGION        DISCOUNT     GROWTH RATE     VALUATIONS                GEOGRAPHIC  SUB-   
                                               RATE     /EBIT MULTIPLE   LO         HI     AVERAGE     TOTAL   TOTALS
- ---------------------------------------------------------------------------------------------------------------------
                                                                                   
BIOPESTICIDES        -           -         10.0%-14.0%       6 -  12    $    4 -  $    6   $    5    $    5   $    5 

SOILSERV             -           -         10.0%-14.0%       6 -  12    $   28 -  $   47   $   37    $   37   $   37 

CONVEN. SEED
                   Corn        N. America  11.0%-21.0%       6 -  12    $   44 -  $  295   $  170  
                               Argentina   11.0%-21.0%       6 -  12    $   20 -  $   61   $   41  
                               Brazil      11.0%-21.0%       6 -  12    $   39 -  $  189   $  114  
                   Soybeans    N. America  11.0%-21.0%       6 -  12    $  (20)-  $   36   $    8  
                               Brazil      11.0%-21.0%       6 -  12    $    0 -  $    0   $    0  
                   Sorghum     N. America  11.0%-21.0%       6 -  12    $    4 -  $   16   $   10  
                   Alfalfa     N. America  11.0%-21.0%       6 -  12    $   (2)-  $   11   $    5  
                   Sunflower   N. America  11.0%-21.0%       6 -  12    $   (4)-  $   (5)  $   (4) 
                               Argentina   11.0%-21.0%       6 -  12    $    7 -  $   25   $   16  
                   All         N. America  11.0%-21.0%       6 -  12    $   29 -  $  361             $  195
                               Argentina   11.0%-21.0%       6 -  12    $   25 -  $   86             $   55
                               Brazil      11.0%-21.0%       6 -  12    $   39 -  $  189             $  114
                                                                                  TOTAL CONVENTIONAL SEED     $  364
                                                                                 
EARLY/INPUT TRAITS                                                               
                   Corn        N. America  20.0%-30.0%   8.0% - 14.0%   $   42 -  $  255   $  148
                               Argentina   20.0%-30.0%   8.0% - 14.0%   $   (0)-  $   14   $    7
                               Brazil      20.0%-30.0%   8.0% - 14.0%   $   16 -  $  112   $   64
                   Soybeans    N. America  25.0%-45.0%   8.0% - 14.0%   $   10 -  $   59   $   34
                               Brazil      25.0%-45.0%   8.0% - 14.0%   $   (1)-  $    0   $  (30)
                   Sunflower   N. America  20.0%-30.0%   8.0% - 14.0%   $   (2)-  $   (0)  $   (1)
                               Argentina   20.0%-30.0%   8.0% - 14.0%   $   (2)-  $    9   $    4
                   All         N. America  20.0%-30.0%   8.0% - 14.0%   $   68 -  $  390             $  229
                               Argentina   20.0%-30.0%   8.0% - 14.0%   $    2 -  $   23             $   10
                               Brazil      20.0%-30.0%   8.0% - 14.0%   $   15 -  $  116             $   66
                                                                                       TOTAL EARLY TRAITS     $  305

OUTPUT TRAITS
                   Corn        N. America  25.0%-45.0%    1.0% -  2.5%  $   (1)-  $   14   $    6
                               Argentina   25.0%-45.0%    8.0% - 14.0%  $   (2)-  $   (0)  $   (1)
                               Brazil      25.0%-45.0%    1.0% -  2.5%  $   (0)-  $    9   $    4
                   Soybean     N. America  25.0%-45.0%    1.0% -  2.5%  $   34 -  $  225   $  129
                               Brazil      25.0%-45.0%    1.0% -  2.5%  $    1 -  $   24   $   12
                   Sunflower   N. America  25.0%-45.0%    1.0% -  2.5%  $    1 -  $    7   $    4
                               Argentina   25.0%-45.0%    8.0% - 14.0%  $    4 -  $   31   $   17
                   All         N. America  25.0%-45.0%    1.0% -  2.5%  $   34 -  $  245             $  140         
                               Argentina   25.0%-45.0%    8.0% - 14.0%  $    2 -  $   30             $   16         
                               Brazil      25.0%-45.0%    1.0% -  2.5%  $    2 -  $   22             $   12         
                                                                                      TOTAL OUTPUT TRAITS     $  168

DISEASE RESISTANCE
                               N. America  40.0%-60.0%   25.0% - 31.0%  $   (2)-  $    1   $   (0)   $   (0)
                               Argentina   40.0%-60.0%   25.0% - 31.0%  $    0 -  $    2   $    1    $    1
                               Brazil      40.0%-60.0%   25.0% - 31.0%  $   (0)-  $   (0)  $   (0)   $   (0)
                                                                       TOTAL DISEASE RESISTANCE               $    1

JV/ROYALTIES
    VMO            Conventional Seed       11.0%-21.0%      6  -   12   $    5 -  $   13   $    9                   
                   Early/Input Traits      15.0%-25.0%    0.0% -  1.5%  $   (1)-  $   (2)  $   (2)                  
                   Output Traits           25.0%-45.0%   14.0% - 20.0%  $    0 -  $   15   $    8                   
                   Disease-Res.            40.0%-60.0%   25.0% - 31.0%  $   (0)-  $    1   $    0                   
                                                             TOTAL VMO  $    4    $   27             $   15   $   15

    JG Boswell     Cotton                  10.0%-12.0%       6 -   12   $   58 -  $  100   $   79    $   79   $   79

    Humko          Oilseed     N. America  10.0%-14.0%       8 -   14   $    0 -  $    0   $    0    $    0
                               Argentina   10.0%-14.0%       8 -   14   $    2 -  $    3   $    3    $    3
                                                         TOTAL OILSEED  $    0 -  $    0                      $    3

    DAS Canada     Canola                  10.0%-14.0%       4 -   10   $   19 -  $   40   $   29    $   29   $   29
    PHB Bt Royalties                       20.0%-30.0%                  $   31 -  $   38   $   34    $   34   $   34
    Other Partner Royalties                20.0%-30.0%    0.0% -  1.5%  $    8 -  $   20   $   14    $   14   $   14
    Other Pests/Crops                      30.0%-50.0%   14.0% - 20.0%  $   24 -  $  238   $  131    $  131   $  131
    Disease Resistance
                 - All Other Crops         40.0%-60.0%   25.0% - 31.0%  $   80 -  $  313   $  196    $  196   $  196
                 - Rice (Japan Tobacco)    30.0%-50.0%   14.0% - 20.0%  $  (2) -  $    8   $    3    $    3   $    3

MISCELLANEOUS

      NOL-Current (est)                                                 $   50 -  $   70   $   60    $   60         
      NOL-Projected (est)                                               $   30 -  $   30   $   30    $   30         
      Monsanto Settlement                                               $    0 -  $  174   $   87    $   87         
      35% in Verneuil (est.)                                            $   33 -  $   66   $   50    $   50         
      Bt FTO                               30.0%-50.0%                  $  101 -  $  179   $  140    $  140         
      Net Debt                                                          $  (75)-  $  (75)  $  (75)   $  (75)  $  (75)
                                                                                                              $  363
                                                                        ------    ------   ------    ------   ------
TOTAL                                                                   $  809    $2,199   $1,624    $1,674   $1,674


    Shares Outstanding (MM)      36.11
VALUE/SHARE                                                             $22.41    $60.91   $44.99    $46.37


- --------------------------------------------------------------------------------------------------------------------


                                                      WASSERSTEIN PERELLA & CO.
- -------------------------------------------------------------------------------



MYCOGEN                                                 VALUATION: DCF ANALYSIS
- -------------------------------------------------------------------------------
VALUATION OF BUSINESS

Pie Chart of Conventional Seed
Contribution to Value


                 
     North America  53.6%
     Brazil         31.3%
     Argentina      15.1%


Pie Chart of Early Traits
Contribution to Value


                 
     North America  75.1%
     Brazil         21.6%
     Argentina       3.3%



Pie Chart of Output Traits
Contribution to Value



                 
     North America  83.4%
     Brazil          7.1%
     Argentina       9.5%



BAR CHART



                
Conventional Seed
     Corn          $  325
     Soybean            8
     Sunflower         12
     Other             15
                   ------
     Total         $  360

Early Traits
     Corn          $  219
     Soybean           34
     Sunflower          3
                   ------
     Total         $  256

Output Traits
     Corn          $    9
     Soybean          141
     Sunflower         21
                   ------
     Total         $  171

Disease Resistance (All Crops)
     New           $  193
     Current            1
                   ------
     Total         $  194

Other Businesses
     Biopesticides $    5
     Soil Serv.        37
                   ------
     Total         $   42

Current JV
     Humko         $    3
     Boswell           79
     VMO               15
                   ------
     Total         $   97

DAS Collaboration
     Rice/Japan
       Tobacco     $    3
     Canola/
       DAS Canola      29
                   ------
     Total         $   32

Royalties
     Other 
       Partners    $   14
     Pioneer Bt        34
                   ------
     Total         $   48

New Pest-Resistant Crops
     Total         $  131

Operating Value
     Total         $1,331

NOL
     Projected     $   29
     Current           65
                   ------
     Total         $   90

Monsanto Settlement
     Total         $   87

35% Stake in Verneuil
     Total         $   50

Bt FTO Fees
     Total         $  140

Net Debt
     Total         $  (75)

Total Value
     Total         $1,624

Miscellaneous
 Items             $  292

VALUATION/SHARE

                   $44.99




                                                       WASSERSTEIN PERELLA & CO.
- --------------------------------------------------------------------------------



MYCOGEN CORPORATION
- --------------------------------------------------------------------------------





                          -------------------------------


                              VALUATION: COMPARABLE
                             COMPANY TRADING ANALYSIS


                          -------------------------------






                                                      WASSERSTEIN PERELLA & CO.
- -------------------------------------------------------------------------------



MYCOGEN CORPORATION               VALUATION: COMPARABLE COMPANY TRADING ANALYSIS
- --------------------------------------------------------------------------------
SELECTED SEED COMPARABLE COMPANIES ANALYSIS

TRADING STATISTICS



                     CURRENT    EQUITY    ADJUSTED  PRICE/EARNINGS   EST. 3-5   98E P/E/
                      PRICE     MARKET     MARKET   --------------   YR. EPS    3-5 YEAR   PRICE/
COMPANY              6/22/98    VALUE      VALUE     1997  1998E       GTH.    EPS GTH(1)   BOOK
- ----------           -------   --------   --------   ----  -----    ---------  ----------  ------
                     (IN $)    (IN $MM)   (IN $MM)   (%)     (%)       (%)        (%)        (%)
                                                                   
Mycogen               23.38      894.4      908.0      NM     NM      22.5        NM         4.3
Pioneer Hi-Bred       39.00    9,525.3    9,044.3    39.6   34.0      15.0       2.27        8.2
Dekalb Genetics       94.19    3,372.4    3,482.4   117.0  120.8      25.0       4.83       15.1
Delta & Pine Land     44.44    1,742.8    1,818.6    90.0   69.4      30.0       2.31       22.2
Agribiotech (1)       28.63      966.9      965.5      NM  119.3      40.0       2.98       12.0

                                     ----------------------------------------------------------
                                     Mean            82.2   85.9      27.5       3.10      14.4
                                     Median          90.0   94.4      27.5       2.65      13.6
                                     High           117.0  120.8      40.0       4.83      22.2
                                     Low             39.6   34.0      15.0       2.27       8.2
                                     ----------------------------------------------------------


                                                      ADJUSTED MARKET VALUE/
                     -------------------------------------------------------------------------------------  Net Debt/
                      1997    LTM   1998E  1999E   1997    LTM    1998E   1999E   1997  LTM   1998E  1999E   MARKET
COMPANY               SALES  SALES  SALES  SALES  EBITDA  EBITDA  EBITDA  EBITDA  EBIT  EBIT   EBIT   EBIT    CAP.
- ----------            -----  -----  -----  -----  ------  ------  ------  ------  ----  ----  -----  -----  ---------
                       (%)    (%)    (%)    (%)     (%)     (%)     (%)     (%)    (%)   (%)   (%)    (%)     (%) 
                                                                     
Mycogen                4.30   4.24   3.87   3.67      NM      NM    81.1    90.8    NM    NM     NM    NM     1.5
Pioner Hi-Bred         5.07   4.99   4.67   4.36    20.0    20.1    17.4    14.8  24.9  25.3   20.9  17.4    (5.1)
Dekalb Genetics        7.71   7.43   7.30   6.57    57.0    54.9    56.2    44.6  73.6  71.5   74.1  58.0     3.3
Delta & Pine Land      9.92   9.42   6.86   5.13    48.9    47.4    32.0    21.6  56.6  56.3   35.8  23.2     4.3
Agribiotech (1)        3.48   3.48   3.79   1.89    84.2    84.2    84.5    32.8    NM    NM     NM  37.0    (O.1)

       ------------------------------------------------------------------------------------------------------------
       Mean            6.55   6.33   5.65   4.49    52.5    51.7    47.5    28.5  51.7  51.0   43.6  33.9     0.6
       Median          6.39   6.21   5.76   4.74    53.0    51.2    44.1    27.2  56.6  56.3   35.8  30.1     1.6
       High            9.92   9.42   7.30   6.57    84.2    84.2    84.5    44.6  73.6  71.5   74.1  58.0     4.3
       Low             3.48   3.48   3.79   1.89    20.0    20.1    17.4    14.8  24.9  25.3   20.9  17.4    (5.1)
       ------------------------------------------------------------------------------------------------------------


OPERATING STATISTICS



                          TOTAL REVENUES
                     ------------------------             EBITDA MARGIN                    EBIT MARGIN
                        LTM     97/96%  98E/97%   ----------------------------    ----------------------------
COMPANY                AMOUNT   GROWTH  GROWTH    1997    LTM    1998E   1999E    1997    LTM    1998E   1999E
- ------------         ---------  ------  ------    ----   -----   -----   -----    ----   -----   -----   -----
                     (In $ MM)    (%)    (%)       (%)    (%)      (%)    (%)      (%)    (%)     (%)    (%)  
                                                                        
Mycogen                    214    35.6    11.2     3.4     2.0     4.8     4.0      NM      NM      NM     0.0
Pioneer Hi-Bred          1,811     3.7     8.7    25.3    24.8    26.8    29.4    20.3    19.8    22.4    25.1
Dekalb Genetics            469    16.5     5.7    13.5    13.5    13.0    14.7    10.5    10.4     9.9    11.3
Delta & Pine Land          193    19.6    44.8    20.3    19.9    21.4    23.8    17.5    16.7    19.1    22.1
Agribiotech (1)            277      NA    (8.1)    4.1     4.1     4.5     5.8     2.1     2.1     3.4     5.1

                     -----------------------------------------------------------------------------------------
                     Mean         13.2    12.8    15.8    15.6    16.4    18.4    12.6    12.3    13.7    15.9
                     Median       16.5     7.2    16.9    16.7    17.2    19.2    14.0    13.6    14.5    16.7
                     High         19.6    44.8    25.3    24.8    26.8    29.4    20.3    19.8    22.4    25.1
                     Low           3.7    (8.1)    4.1     4.1     4.5     5.8     2.1     2.1     3.4     5.1
                     -----------------------------------------------------------------------------------------



                             NET INCOME MARGIN                       R&D/TOTAL REVENUES
                   ------------------------------------     -----------------------------------
                     1997     LTM     1998E      1999E        1997        1998E         1999E
                   --------  ------   -----     -------     --------    ---------      --------
                     (%)      (%)      (%)        (%)          (%)         (%)            (%)
Mycogen               NM       NM       NM         NM          11.4         NA            NA
Pioneer Hi-Bred     13.6     12.9     15.0       16.9           8.2        7.7           7.8
Dekalb Genetics      6.4      6.9      6.1        7.1          12.7       12.6          15.1
Delta & Pine Land   10.7     10.1     10.1       11.8           7.4        6.1           4.7
Agribiotech (1)       NM       NM      1.9        2.3            NA         NA            NA


                     -------------------------------------------------------------
                     Mean         10.2     10.0    8.3    9.5    9.4    1.8    9.3
                     Median       10.7     10.1    8.1    9.4    8.2    7.7    7.8
                     High         13.6     12.9   15.0   16.9   12.7   12.6   15.1
                     Low           6.4      6.9    1.9    2.3    7.4    6.1    4.7
                     -------------------------------------------------------------



- -----------------------
1997 data refers to FYE 8/31/97, etc. All means and medians exclude Mycogen.
Currency are converted at current exchange rates.
EPS projections are based on I/B/E/S consensus; other projections are based on 
 selected brokers' research.
When not available, depreciation and amortization are estimated as a percentage 
 of sales based on the latest released data.
When not available, LTM data is based on selected brokers' research.
(1) Represents ratio of the 1998E P/E ratio to the estimated 3-5 year earnings 
    growth rate.
(2) Agribiotech fiscal year end 6/30. LTM data represents financials for 1997 
    fiscal year end pro forma for acquisitions. EBITDA estimated per analyst 
    projections of D&A margins.


                                                       WASSERSTEIN PERELLA & CO.
- --------------------------------------------------------------------------------



MYCOGEN CORPORATION               VALUATION: COMPARABLE COMPANY TRADING ANALYSIS
- --------------------------------------------------------------------------------
SELECTED AG-BIOTECHNOLOGY COMPARABLE COMPANIES ANALYSIS FOR 
FISCAL YEAR 1994-1997



                               EBITDA MARGIN                            EBIT MARGIN               
                   ------------------------------------     ------------------------------------  
                     1994      1995      1996     1997        1994      1995     1996     1997    
                     ----      ----      ----     ----        ----      ----     ----     ----    
                                                                       
Mycogen              (5.3%)    (5.8%)   (8.7%)     3.4%      (11.0%)   (13.7%)  (14.5%)   (1.3%)  
Pioneer Hi-Bred      25.4%     23.1%    24.6%     25.3%       20.4%     18.3%    20.2%    20.3%   
Dekalb Genetics      10.2%     11.1%    11.4%     13.5%        6.6%      7.6%     8.5%    10.5%   
Delta & Pine Land    19.3%     22.5%    20.4%     20.3%       16.1%     19.4%    17.7%    17.5%   
Agribiotech (1)        NM     (27.0%)   (9.0%)    (0.7%)        NM     (29.9%)  (11.2%)   (2.4%)  
                                                                                                  
          ----------------------------------------------------------------------------------------
          MEAN       18.3%      7.4%    11.8%     14.6%       14.4%      3.8%     8.8%    11.5%   
          MEDIAN     19.3%     16.8%    15.9%     16.9%       16.1%     12.9%    13.1%    14.0%   
          ----------------------------------------------------------------------------------------



                              NET INCOME MARGIN                       R&D/TOTAL REVENUES        
                    ------------------------------------     -----------------------------------
                      1994      1995      1996     1997        1994      1995     1996     1997 
                      ----      ----      ----     ----        ----      ----     ----     ---- 
                                                                     
Mycogen               (8.8%)   (14.1%)  (19.6%)   (8.5%)       16.1%     18.7%    15.2%    11.4%

Pioneer Hi-Bred       12.4%     11.9%    13.0%    13.6%         7.7%      8.5%     7.9%     8.2%
Dekalb Genetics        3.5%      3.0%     4.4%     6.4%        13.8%     13.3%    12.3%    12.7%
Delta & Pine Land      9.7%     11.1%    10.5%    10.7%         6.8%      6.7%     6.4%     7.4%
Agribiotech (1)         NM     (29.6%)  (12.8%)   (4.1%)         NM       1.2%     0.2%     1.8%
                                                                                                
          --------------------------------------------------------------------------------------
          MEAN         8.6%     (0.9%)    3.8%     6.7%         9.4%      7.4%     6.7%     7.5%
          MEDIAN       9.7%      7.0%     7.4%     8.6%         7.7%      7.6%     7.1%     7.8%
          --------------------------------------------------------------------------------------



                            Selling/Total Revenues                      G & A Margin
                   ------------------------------------     -----------------------------------
                     1994      1995      1996     1997        1994      1995     1996     1997
                     ----      ----      ----     ----        ----      ----     ----     ----
                                                                 
Mycogen              22.4%     20.8%     24.3%    19.8%       14.9%     11.7%    12.7%     8.5%

Pioneer Hi-Bred      22.7%     23.1%     22.2%    21.0%        8.3%      8.2%     7.5%     7.3%
Dekalb Genetics      19.3%     20.2%     18.8%    18.2%        5.7%      8.1%     8.3%     7.6%
Delta & Pine Land     7.2%      7.7%      6.2%     6.0%       10.1%      9.7%     6.1%     5.5%
Agribiotech (1)         NA        NA        NA       NA          NA        NA       NA       NA

          -------------------------------------------------------------------------------------
          MEAN       16.4%     17.0%     15.7%    15.1%        8.0%      8.7%     7.3%     6.8%
          MEDIAN     19.3%     20.2%     18.8%    18.2%        8.3%      8.2%     7.5%     7.3%
          -------------------------------------------------------------------------------------




                                  Days Receivable                          Days of Inventory
                        ------------------------------------      -----------------------------------
                        1994       1995     1996       1997       1994       1995     1996       1997
                        -----     -----     -----      -----      -----     -----     -----     -----
                                                                      
Mycogen                    86        89        70         70        182       181       143       162

Pioneer Hi-Bred            39        38        44         52        213       239       189       205
Dekalb Genetics (2) (3)    53        65        48         42        218       235       177       217
Delta & Pine Land          11        19       157        187        144       130       153       133
Agribiotech (1)            NM        54       104         95         NM       145       136       170


             -----------------------------------------------------------------------------------------
               MEAN        34        44        88         94        192       187       164        181
               MEDIAN      39        46        76         74        213       190       165        188
             -----------------------------------------------------------------------------------------



                                   Days Payable                          Net Debt/Book Equity
                        ------------------------------------      -----------------------------------
                        1994       1995     1996       1997       1994       1995     1996       1997
                        -----     -----     -----      -----      -----     -----     -----     -----
                                                                       
Mycogen                    22        36        33         60      (30.2%)  (13.5%)    (36.7%)    19.5%
                       
Pioneer Hi-Bred            48        33        44         40       (6.1%)     4.9%     (4.8%)     1.7%
Dekalb Genetics (2) (3)    14        15        24         24       102.1%    98.8%      36.6%    60.8%
Delta & Pine Land          28        40        55         59        31.8%    11.0%      48.3%    39.9%
Agribiotech (1)            NM        56        82         77      (45.4%)   (9.3%)      29.9%    56.4%

             ----------------------------------------------------------------------------------------
               MEAN       30        36        51         50        20.6%    26.4%      27.5%    39.7%
               MEDIAN     28        36        50         49        12.8%     8.0%      33.2%    48.2%
             ----------------------------------------------------------------------------------------



- -------------------------------
NOTE: DAYS CALCULATION ASSUMES 360-DAY A YEAR AND ALL MEANS AND MEDIANS 
EXCLUDE MYCOGEN DATA
(1)  Agribiotech changed its fiscal year end in 1995. 1995 data are based on 
nine-month period ended 6/30/95. 1997 data are not pro forma of acquisition 
because no pro forma balance sheet number available for ratio calculations
(2)  Data not available to separate trade receivables from note receivables
(3)  Accounts Payable includes only trade accounts payable

                                                       WASSERSTEIN PERELLA & CO.
- --------------------------------------------------------------------------------



MYCOGEN CORPORATION               VALUATION: COMPARABLE COMPANY TRADING ANALYSIS
- --------------------------------------------------------------------------------
SELECTED COMPARABLE COMPANIES QUARTERLY ANALYSIS FOR FISCAL YEAR 1997




                                   EBITDA Margin                             EBIT Margin
                        ------------------------------------      -----------------------------------
                        1-Qtr     2-Qtr     3-Qtr      4-Qtr      1-Qtr     2-Qtr     3-Qtr     4-Qtr
                        -----     -----     -----      -----      -----     -----     -----     -----
                                                                     
Mycogen                (44.7%)     8.3%     13.5%     (6.2%)     (55.4%)      5.5%     10.6%   (16.4%)
 
Pioneer Hi-Bred        (57.8%)     6.1%     41.8%     (35.2%)    (78.9%)    (2.3%)     40.0%   (52.8%)
Dekalb Genetics          11.0%    16.1%     14.2%     (19.4%)       6.4%     14.5%     12.5%    (53.0%
Delta & Pine Land      (82.8%)    25.2%     29.5%          NM   (101.6%)     23.3%     28.4%        NM
Agribiotech (1)        (14.0%)   (4.1%)      8.6%      (2.3%)    (16.4%)    (6.1%)      7.0%     (3.8%)

             ------------------------------------------------------------------------------------------
               MEAN    (35.9%)    10.8%     23.5%     (19.0%)    (47.6%)      7.4%     22.0%    (36.5%)
               MEDIAN  (35.9%)    11.1%     21.8%     (19.4%)    (47.7%)      6.1%     20.4%    (52.8%)
             ------------------------------------------------------------------------------------------



                                 Net Income Margin                        R&D/Total Revenues
                        ------------------------------------      -----------------------------------
                        1-Qtr     2-Qtr     3-Qtr      4-Qtr      1-Qtr     2-Qtr     3-Qtr     4-Qtr
                        -----     -----     -----      -----      -----     -----     -----     -----
                                                                      
Mycogen                (54.7%)     3.7%      6.8%     (48.4%)     26.3%      7.8%      6.9%     22.3%

Pioneer Hi-Bred        (50.0%)   (0.8%)     25.8%     (29.6%)     33.3%     12.5%      3.1%     30.3%
Dekalb Genetics           3.1%     8.5%      7.3%     (20.1%)      8.9%     13.2%     12.8%     23.1%
Delta & Pine Land      (65.5%)    14.1%     17.9%         NM      41.0%      5.2%      3.3%        NM
Agribiotech (1)        (16.9%)   (8.9%)      6.4%      (6.2%)      1.2%      2.1%      1.4%      2.0%

             ------------------------------------------------------------------------------------------
               MEAN    (32.3%)     3.2%     14.3%     (18.6%)     21.1%      8.3%      5.2%     18.5%
               MEDIAN  (33.5%)     3.9%     12.6%     (20.1%)     21.1%      8.8%      3.2%     23.1%
             ------------------------------------------------------------------------------------------



                                  Days Receivable                          Days of Inventory
                        ------------------------------------      -----------------------------------
                        1-Qtr     2-Qtr     3-Qtr      4-Qtr      1-Qtr     2-Qtr     3-Qtr     4-Qtr
                        -----     -----     -----      -----      -----     -----     -----     -----
                                                                      
Mycogen (2) (3)           129        61        85        109        761       145        89       257

Pioneer Hi-Bred (2)       178        79        34        162      1,490       515        68       558
Dekalb Genetics (2) (4)    69        33        79        357        526       147        97     1,361
Delta & Pine Land          92        99        99         NM      1,067       144        50        NM
Agribiotech (1)            97        61        81         64        289       189       122       113


             ------------------------------------------------------------------------------------------
               MEAN      109        68        73        194        843       249        84       677
               MEDIAN     94        70        80        162        796       168        83       558
             ------------------------------------------------------------------------------------------



                                   Days Payable                          Net Debt/Book Equity
                        ------------------------------------      -----------------------------------
                        1-Qtr     2-Qtr     3-Qtr      4-Qtr      1-Qtr     2-Qtr     3-Qtr     4-Qtr
                        -----     -----     -----      -----      -----     -----     -----     -----
                                                                         
Mycogen (2) (3)           216        40        25         95      (3.4%)      8.4%     24.5%     19.5%
Pioneer Hi-Bred (2)       718       147        29        108       19.3%   (30.8%)    (9.7%)      1.7%
Dekalb Genetics (2) (4)   249        44        11        153       71.8%     35.7%     72.4%     60.8%
Delta & Pine Land         314        38        12         NM       66.1%    103.1%     34.7%     39.9%
Agribiotech (1)           104        92        64         52     (16.8%)     60.4%     64.3%     56.4%

             ------------------------------------------------------------------------------------------
               MEAN      346        80        29        104       35.1%     42.1%     40.4%     39.7%
               MEDIAN    281        68        21        108       42.7%     48.0%     49.5%     48.2%
             ------------------------------------------------------------------------------------------



NOTE: DAYS CALCULATION ASSUMES 360-DAY A YEAR AND ALL MEANS AND MEDIANS EXCLUDE
      MYCOGEN DATA
(1) Agribiotech data are not pro forma of acquisition
(2) Data not available to separate notes receivable from accounts receivable for
    quarterly data
(3) 2nd and 3rd quarter net debts include $14.25 million unsecured note payable 
    to bank that was specified in the 10-K
(4) Accounts Payable includes only trade accounts payable


                                                       WASSERSTEIN PERELLA & CO.
- --------------------------------------------------------------------------------



MYCOGEN CORPORATION               VALUATION: COMPARABLE COMPANY TRADING ANALYSIS
- --------------------------------------------------------------------------------
SELECTED AG-BIOTECHNOLOGY COMPARABLE COMPANIES ANALYSIS


TRADING STATISTICS


                Current  Equity   Adjusted  Price Earnings  Est. 3-5  98E P/E
                 Price   Market    Market   --------------  yr. EPS   3-5 Year   Price/ 
Company         6/22/98  Value     Value     1997  1998E      Gth.   EPS Gth (1)   Book  
- ----------      ------- --------  --------   ----  -----   --------- ----------  ------ 
                (In $)  (In $MM)  (In $MM)   (%)    (%)      (%)        (%)       (%)   
                                                         
Mycogen          23.38    894.4     908.0      NM    NM      22.5       NM        4.3   
DNAP Holding      4.38     76.9     126.4    39.6    NA        NA       NM        2.8   
Ecogen (2)        2.88     23.0      22.0      NM    NM        NA       NM        4.1   

                                   Mean      39.6    NA        NA       NA        3.4   
                                   Median    39.6    NA        NA       NA        3.4   
                                   High      39.6    NA        NA       NA        4.1   
                                   Low       39.6    NA        NA       NA        2.8    




                                                       Adjusted Market Value
                ----------------------------------------------------------------------------------  Net Debt/  
                 1997    LTM   1998E  1999E  1997   LTM   1998E   1999E   1997  LTM   1998E  1999E   Market    
Company          Sales  Sales  Sales  Sales EBITDA EBITDA EBITDA  EBITDA  EBIT  EBIT   EBIT   EBIT    Cap.     
- ----------       -----  -----  -----  ----- ------ ------ ------  ------  ----  ----  -----  -----  ---------  
                  (%)    (%)    (%)    (%)    (%)    (%)    (%)     (%)    (%)   (%)    (%)   (%)     (%) 
                                                              
Mycogen           4.30   4.24   3.87  3.67     NM     NM    81.1   90.8     NM    NM     NM    NM      1.5
DNAP Holding      0.45   0.46     NA    NA     NM     NM      NA     NA     NM    NM     NA    NA     63.1
Ecogen (2)        1.88   1.47     NA    NA     NM     NM      NM     NM     NM    NM     NM    NM     (4.2)     
                                                                                                               
                                                                                                               
      Mean        1.17   0.96     NA    NA     NA     NA      NA     NA     NA    NA     NA    NA     29.5      
      Median      1.17   0.96     NA    NA     NA     NA      NA     NA     NA    NA     NA    NA     29.5      
      High        1.88   1.47     NA    NA     NA     NA      NA     NA     NA    NA     NA    NA     63.1      
      Low         0.45   0.46     NA    NA     NA     NA      NA     NA     NA    NA     NA    NA     (4.2)     



OPERATING STATISTICS



                           TOTAL REVENUES
                      ------------------------           EBIDTA Margin                  EBIDTA Margin         
                         LTM  97/96%  98E/97%     -----------------------------    -------------------------  
Company                 Amount   Growth  Growth   1997    LTM    1998E    1999E    1997   LTM   1998E  1999E  
- ------------          ---------  ------  ------   ----    ----   -----    -----    ----  -----  -----  -----   
                      (In $ MM)    (%)    (%)      (%)    (%)      (%)     (%)      (%)   (%)    (%)   (%)    
                                                                      
Mycogen                    214    35.6    11.2     3.4    2.0      4.8     4.0      NM      NM    NM    0.0   
DNAP Holding               275    45.7      NA      NM     NM       NA      NA      NM      NM    NA     NA   
Ecogen (2)                  15     9.5      NA      NM     NM       NA      NA      NM      NM    NA     NA   

                       Mean       27.6      NA      NA     NA       NA      NA      NA      NA    NA     NA   
                       Median     27.6      NA      NA     NA       NA      NA      NA      NA    NA     NA   
                       High       45.7      NA      NA     NA       NA      NA      NA      NA    NA     NA   
                       Low         9.5      NA      NA     NA       NA      NA      NA      NA    NA     NA   





                     EBIDTA Margin            NET Income Margin        R&D/Total Revenues
               --------------------------  --------------------------  ------------------
Company        1997   LTM    1998E  1999E  1997   LTM   1998E   1999E  1997  1998E  1999E
- ------------   ----  -----  -----   -----  ----  -----  -----   -----  -----  ----  -----
                                                    
                (%)   (%)    (%)     (%)    (%)   (%)    (%)     (%)    (%)    (%)    (%) 
Mycogen          NM    NM     NM     0.0     NM    NM     NM      NM    11.4    NA     NA 
DNAP Holding     NM    NM     NA      NA     NM    NM     NA      NA     2.8    NA     NA 
Ecogen (2)       NM    NM     NA      NA     NM    NM     NA      NA    32.6    NA     NA 
                                                                                         
 Mean            NA    NA     NA      NA     NA    NA     NA      NA    17.7    NA     NA 
 Median          NA    NA     NA      NA     NA    NA     NA      NA    17.7    NA     NA 
 High            NA    NA     NA      NA     NA    NA     NA      NA    32.6    NA     NA 
 Low             NA    NA     NA      NA     NA    NA     NA      NA     2.8    NA     NA 


- -----------------------
1997 data refers to FYE 8/31/97, etc. All means and medians exclude Mycogen.
Currency are converted at current exchanges rates.
EPS projections are based on I/B/E/S consensus; other projections are based on 
 selected brokers' research.
When not available, depreciation and amortization are estimated as a percentage 
 of sales based on the latest released data.
When not available, LTM data is based on selected brokers' research.
(1) Represents ratio of the 1998E P/E ratio to the estimated 3.5 year earnings 
    growth rate.
(2) Ecogen fiscal year end 10/31.


                                                       WASSERSTEIN PERELLA & CO.
- --------------------------------------------------------------------------------



MYCOGEN CORPORATION               VALUATION: COMPARABLE COMPANY TRADING ANALYSIS
- --------------------------------------------------------------------------------
SELECTED AG-BIOTECHNOLOGY COMPARABLE COMPANIES ANALYSIS FOR 
FISCAL YEAR 1994-1997



                               EBITDA MARGIN                            EBIT MARGIN
                   ------------------------------------     -----------------------------------
                     1994      1995      1996     1997        1994      1995     1996     1997
                     ----      ----      ----     ----        ----      ----     ----     ----
                                                                 
Mycogen              (5.3%)    (5.8%)   (8.7%)     3.4%      (11.0%)   (13.7%)  (14.5%)   (1.3%)

DNAP Holding (1)    (12.9%)      4.0%   (5.9%)   (4.3%)      (18.0%)      2.3%   (7.6%)   (6.6%)
Ecogen (1)(2)      (174.2%)  (114.4%)  (19.4%)  (59.0%)     (179.1%)  (119.8%)  (22.0%)  (70.6%)


          --------------------------------------------------------------------------------------
          MEAN      (93.6%)   (55.2%)  (12.7%)  (31.7%)      (98.6%)   (58.7%)  (14.8%)  (38.6%)
          MEDIAN    (93.6%)   (55.2%)  (12.7%)  (31.7%)      (98.6%)   (58.7%)  (14.8%)  (38.6%)
          --------------------------------------------------------------------------------------


                             NET INCOME MARGIN                       R&D/TOTAL REVENUES
                   ------------------------------------     -----------------------------------
                     1994      1995      1996     1997        1994      1995     1996     1997
                     ----      ----      ----     ----        ----      ----     ----     ----
                                                                 
Mycogen              (8.8%)   (14.1%)  (19.6%)   (8.5%)       16.1%     18.7%    15.2%    11.4%

DNAP Holding (1)    (10.6%)    (1.9%)   (8.8%)   (7.2%)        0.0%      0.0%     7.3%     2.8%
Ecogen (1)(2)      (171.5%)  (148.7%)  (17.5%)  (75.1%)       37.6%     63.6%    25.1%    32.6%


          --------------------------------------------------------------------------------------
          MEAN      (91.0%)   (75.3%)  (13.1%)  (41.2%)       18.8%     31.8%    16.2%    17.7%
          MEDIAN    (91.0%)   (75.3%)  (13.1%)  (41.2%)       18.8%     31.8%    16.2%    17.7%
          --------------------------------------------------------------------------------------





                              DAYS RECEIVABLE                        DAYS OF INVENTORY
                   ------------------------------------     -----------------------------------
                     1994      1995      1996     1997        1994      1995     1996     1997
                     ----      ----      ----     ----        ----      ----     ----     ----
                                                                 
Mycogen                86        89        70       70         182       181      143      162

DNAP Holding (2)       NA        45        51       38          NA        30       41       24
Ecogen                 46        23        41       54         403       415      433      478


          --------------------------------------------------------------------------------------
          MEAN         46        34        46       46         403       222      237      251
          MEDIAN       46        34        46       46         403       222      237      251
          --------------------------------------------------------------------------------------



                                DAYS PAYABLE                        NET DEBT/BOOK EQUITY
                   ------------------------------------     -----------------------------------
                     1994      1995      1996     1997        1994      1995     1996     1997
                     ----      ----      ----     ----        ----      ----     ----     ----
                                                                 
Mycogen                22        36        33       60       (30.2%)   (13.5%)  (36.7%)   19.5%

DNAP Holding (2)       NA        34        39       22            NA    276.8%    67.6%   191.9%
Ecogen                 98       179       221      227       (91.5%)   (21.0%)  (57.7%)   31.7%


          --------------------------------------------------------------------------------------
          MEAN         98       107       130      125       (91.5%)    127.9%     4.9%   111.8%
          MEDIAN       98       107       130      125       (91.5%)    127.9%     4.9%   111.8%
          --------------------------------------------------------------------------------------



- ---------------------
NOTE: DAYS CALCULATION ASSUMES 360-DAY A YEAR AND ALL MEANS AND MEDIANS EXCLUDE
    MYCOGEN DATA
(1) R&D expenses includes both self-funded expenses and purchased R&D expenses
(2) Ecogen changed its fiscal year end in 1994. 1994 data are based on ten-month
    period ended 10/31/94
(3) Data not available to separate accounts payable from accrued expenses for
    1995

                                                       WASSERSTEIN PERELLA & CO.
- --------------------------------------------------------------------------------



MYCOGEN CORPORATION                  VALUATION: COMPARABLE ACQUISITION ANALYSIS
- -------------------------------------------------------------------------------
SELECTED COMPARABLE ACQUISITION/VALUATION MULTIPLES



                                                                                              Adjusted Purchase    Implied Value 
                                                                                                    Price/           of Equity/
                                                                                            --------------------   --------------
                                                             Implied Value    Adjusted       LTM      LTM     LTM     Net    Book
Target                         Acquirer           Close Date   of Equity   Purchase Price   Sales    EBITDA  EBIT   Income  Value
- ----------------------------   ------------------ ----------   ---------   --------------   -----   -------  ----   ------  ------
                                                                                                 
SEEDS COMPANIES                                                                                                                  
Delta & Pine Land              Monsanto           Pending     $1,832.5         $1,906.7      9.87 x  69.8 x  89.6 x    NM x  25.1 x
                                                                                                                                 
Sunseeds                       AgrEvo             10/6/97           NA               NA      2.20 x  13.1 x  18.0 x    NA x    NA x
                                                                                                                                 
Pioneer Hi-Bred (16.6% stake)  DuPont             9/18/97     $1,700.0         $1,700.0      4.60 x  18.4 x  22.6 x  33.9 x   8.9 x
                                                                                                                                 
Holden's Foundation Seeds      Monsanto            9/4/97           NA           $975.0(1)  21.67 x    NA x    NA x    NA x    NA x
                                                                                                                                 
Asgrow Corn & Seed             Monsanto            2/4/97           NA           $240.0      1.41 x    NA      NA      NA      NA 
                                                                                                                                 
Morgan Seeds                   Mycogen Corp.      10/1/96        $40.9            $40.9      1.10 x    NA      NA      NA      NA 
                                                                                                                                 
Agracetus (W.R. Grace)         Monsanto           5/21/96       $150.0           $150.0        NA      NA      NA      NA      NA 
                                                                                                                                 
Sure Grow                      Delta & Pine Land 5/21/96         $70.0            $78.9      3.47    17.5    19.1    29.9     3.2 
                                                                                                                                 
Jacobs Hertz Seed (Monsanto)   Delta & Pine Land  2/5/96            NA               NA        NA      NA      NA      NA         
                                                                                                                                 
Cargill - Cotton & Seed        Delta & Pine Land  5/3/94            NA               NA        NA      NA      NA      NA      NA 
                                                                                                                                 
                               -------------------------------------------------------------------
                               MEAN SALES MULTIPLE       (2)                                6.33x
                               MEDIAN SALES MULTIPLE     (2)                                3.47x
                               IMPLIED MYCOGEN ENTERPRISE VALUE RANGE              $743 - $1,355
                               -------------------------------------------------------------------



- ----------------------------------
(1) Final terms not disclosed; purchase price assumes maximum expected price.


                                                      WASSERSTEIN PERELLA & CO.
- -------------------------------------------------------------------------------



MYCOGEN CORPORATION                  VALUATION: COMPARABLE ACQUISITION ANALYSIS
- -------------------------------------------------------------------------------
SELECTED COMPARABLE ACQUISITION/VALUATION MULTIPLES



                                                                                              Adjusted Purchase    Implied Value 
                                                                                                    Price/           of Equity/
                                                                                            --------------------   --------------
                                                             Implied Value    Adjusted       LTM     LTM     LTM     Net    Book
Target                         Acquirer           Close Date   of Equity   Purchase Price   Sales   EBITDA  EBIT   Income  Value
- ----------------------------   ------------------ ----------   ---------   --------------   -----  -------  ----   ------  ------
                                                                                                

BIOTECH COMPANIES (MINORITY STAKES)
Calgene (Minority Buy-In)      Monsanto           5/22/97      $534.1(1)   567.3(1)         2.86 x    NM x    NM x    NM x  6.3 x

Mycogen                        DowElanco          12/4/96      $587.9(1)  $556.7(1)         3.50 x    NM x    NM x    NM x  3.4 x
(1mm shares)

Calgene Inc.                   Monsanto          11/13/96      $573.1(1)  $620.5(1)         6.50 x    NM x    NM x    NM x  6.1 x
(6.25mm shares)

DeKalb Genetics Corp.          Monsanto            3/8/96      $417.3(1)  $533.4(1)         1.70 x  15.9 x  23.4 x  33.4 x  3.1 x
(10% of voting shrs and 8% of non-voting shrs)

Mycogen                        Pioneer Hi-Bred    9/18/95      $257.3(1)  $196.9(1)         1.70 x    NM x    NM x    NM x  2.3 x
(3mm shares)

                               -------------------------------------------------------------------
                               MEAN SALES MULTIPLE                                          3.25 x
                               MEDIAN SALES MULTIPLE                                        2.86 x
                               IMPLIED MYCOGEN ENTERPRISE VALUE RANGE              $611 -   $696
                               -------------------------------------------------------------------


- -----------------------------

(1) Calculated by translating the price that acquiror paid for part of the 
    target into price for the entire company


                                                      WASSERSTEIN PERELLA & CO.
- -------------------------------------------------------------------------------



MYCOGEN CORPORATION                   VALUATION: COMPARABLE ACQUISITION ANALYSIS
- --------------------------------------------------------------------------------
SELECTED COMPARABLE ACQUISITION/VALUATION MULTIPLES (CONT'D)



                                                                                             Adjusted Purchase      Implied Value
                                                                                                    Price/            of Equity/
                                                                                           ---------------------    --------------
                                                            Implied Value    Adjusted       LTM     LTM     LTM       Net   Book
Target                            Acquirer      Close Date    of Equity    Purchase Price  Sales   EBITDA   EBIT    Income  Value
- --------------------------------  ------------  ----------  -------------  --------------  -----   ------   ----    ------  ------
                                                                                                 
BIOTECH COMPANIES (MAJORITY STAKES)
- -----------------------------------

Monsanto                          American Home   Pending(1)  $35,563.7      $39,134.7     5.09 x   36.4 x   70.8 x   NM x    8.1 x
                                  Products

Plant Breeding Int'l (Unilever)   Monsanto        Bidding          NA            NA         NA       NA       NA      NA       NA
 
Dekalb Genetics                   Monsanto        Pending      $3,771.2(2)    $3,881.2(2)  8.28 x   61.2 x   79.7 x   NM x   16.9 x

Zeneca                            Mogen           5/13/97         $73.6          $73.6    12.80 x    NM x      NM x   NM x     NA

Bionova (ELM)                     DNA Plant       9/27/96         $63.4          $67.9       NM x    NM x      NM x   NM x     NA
                                  Tech.

Plant Genetic Systems             AgrEvo          8/30/96        $733.0         $733.0       NM x    NM x      NM x   NM x     NA

Calgene Inc.                      Monsanto         4/1/96        $299.8(2)      $268.0(2)  4.80 x    NM x      NM x   NM x    3.1 x
(49.9% shares)

Mycogen                           DowElanco        3/8/96        $444.7(2)      $358.1(2)  2.90 x    NM x      NM x   NM x    2.3 x
(9.5mm shares)

United AgriSeeds Inc.             Mycogen         2/28/96         $72.4          $72.4       NA       NA        NA      NA     NA

Lubrizol                          Mycogen          1/5/96            NA             NA       NA       NA        NA      NA     NA




- -------------------------------------------------------------------------
                                                       
   MEANS SALES MULTIPLE                                         7.74 x

   MEDIAN SALES MULTIPLE                                        5.09 x

   IMPLIED MYCOGEN ENTERPRISE VALUE RANGE   $1,090  -        $1,657
- -------------------------------------------------------------------------


- --------------------------------------
(1) Monsanto operating data are not pro forma of all announced acquisitions 
    and acquisitions Monsanto is currently bidding

(2) Calculated by translating the price that acquiror paid for part of the 
    target into price for the entire company

                                                      WASSERSTEIN PERELLA & CO.
- -------------------------------------------------------------------------------



MYCOGEN CORPORATION                   VALUATION: COMPARABLE ACQUISITION ANALYSIS
- --------------------------------------------------------------------------------
PREMIUM ANALYSIS FOR ACQUISITIONS BY MAJORITY SHAREHOLDERS WITH DEAL SIZES 
BETWEEN $100MM - $550MM(1)



                                                                                             Seller Closing Price Pre-Announcement/
                                                                    Ann.     Per                      Acquisition Premium
                                                                    Deal    Share           ---------------------------------------
                                                          Ann.      Value    Acq.   % Being   1-Day  30-Day  60-Day  90-Day 120-Day
Acquiror                    Seller                        Date      ($MM)   Price   Acquired  Prem.   Prem.   Prem.   Prem.  Prem.
- --------                    ------                        ----      -----   -----   --------  -----  ------  ------  ------ -------
                                                                                              
Dow                         MYCOGEN CORP. (BIOTECH)         5/1/98  $778.5   $20.50   31.2%    0.0%   12.3%    20.6%   (0.6%)   7.2%

Monsanto Co.                Calgene Inc. (Biotech)         1/28/97   242.6     8.00   43.7%   45.5%   60.0%    45.5%   64.1%   60.0%
Novartis AG                 SyStemix Inc. (Biotech)        5/27/96   119.4    19.50   26.8%   77.3%   59.2%    48.6%   39.3%   52.9%

Investor Group              BET Holdings Inc.              3/17/98  $471.6   $63.00   42.0%    4.0%   17.5%    18.0%   17.8%   20.9%
Telephone and Data Systems  United States Cellular Corp.  12/18/97   539.2    33.00   19.3%    0.0%    1.1%   (5.2%)  (1.3%)   10.5%
Telephone and Data Systems  Aerial Communications Inc.    12/18/97   107.6     8.19   17.5%    0.0%  (1.5%)  (14.9%) (12.7%)    7.4%
Rexel, S.A.                 Rexel, Inc.                    8/29/97   290.1    22.50   49.5%   19.2%   25.9%    25.9%   24.1%   32.4%
Anthem Inc.                 Acordia Inc.                    6/2/97   172.7    40.00   33.2%   12.7%   26.5%    25.5%   26.0%   43.5%
Enron Corp.                 Enron Global Power & Pipelines 5/14/97   428.0    33.83   48.0%   11.8%   20.8%    19.2%   12.8%   24.1%
Petrofina SA                Fina Inc.                      2/25/97   257.0    60.00   14.6%   19.7%   18.2%    24.7%   16.2%   11.1%
Mafco Holdings Inc.         Mafco Consolidated Group       1/21/97   116.8    33.50   15.0%   23.5%   30.1%    17.0%   40.3%   10.3%
Zunich Versicherungs        Zurich Reinsurance Center      1/13/97   319.0    36.00   34.0%   17.1%   12.1%    15.7%   18.5%   17.1%
Andrews Group Inc.          Toy Biz Inc. (2)              11/20/96   208.2    22.50   33.0%   29.5%   20.0%    37.4%   52.5%   31.4%
COBE Laboratories Inc.      REN Corp. - USA                7/14/95   177.7    20.00   47.0%   27.0%   35.6%    29.0%   35.6%   29.6%
BIC SA                      Bic Corp.                      5/19/95   212.6    40.50   22.0%   13.3%   30.1%    28.1%   29.1%   37.9%
Club Mediterranee SA        Club Med Inc.                   4/5/95   153.4    32.00   33.0%   41.4%   45.5%    42.2%   36.2%   35.4%

- -----------------------------------------------------------------------------------------------------------------------------------
Mean                                                                                  31.9%   22.8%   26.7%   23.8%   26.6%   28.3%
Median                                                                                33.0%   19.2%   25.9%   25.5%   26.0%   29.6%
Maximum                                                                               49.5%   77.3%   60.0%   48.6%   64.1%   60.0%
Minimum                                                                               14.6%    0.0%   (1.5%) (14.9%) (12.7%)   7.4%

Mean/Median for Biotech Transactiosn                                                  35.2%   61.4%   59.6%   47.0%   51.7%   56.5%

MYCOGEN CORP. DATA                                                                           $20.50  $18.25  $17.00  $20.63  $19.13
IMPLIED SHARE PRICE BASED ON MEDIAN                                                          $24.44  $22.97  $21.33  $25.98  $24.78
IMPLIED SHARE PRICE BASED ON MEDIAN FOR BIOTECH TRANSACTIONS                                 $33.08  $29.13  $24.99  $31.29  $29.93
- -----------------------------------------------------------------------------------------------------------------------------------


- -------------------------------------------------
(1) Source: Securities Data Company
(2) The deal was later withdrawn

Note: Unless noted, days referred to are calendar days.


                                                      WASSERSTEIN PERELLA & CO.
- -------------------------------------------------------------------------------




                                      5



MYCOGEN CORPORATION
- -----------------------------------------------------------------------------







                         -----------------------------------



                                STRATEGIC ALTERNATIVES      



                         -----------------------------------







                                                    WASSERSTEIN PERELLA & CO.
- -----------------------------------------------------------------------------



MYCOGEN CORPORATION                                      STRATEGIC ALTERNATIVES
- -------------------------------------------------------------------------------
POTENTIAL BUSINESS STRATEGIES

OPTION I

I.    NEGOTIATE A FAIR PRICE FOR THE SALE OF ALL OUTSTANDING SHARES TO DOW

      BENEFITS:

      -  Provides cash payment at attractive share price

      -  Eliminates barriers to full cooperation associated with maintaining 
         two separate public companies

      -  Resources of the combined company would be better able to realize 
         Mycogen's goal of becoming a leading fully integrated developer, 
         manufacturer and marketer of products used to control pests and 
         improve food production

      ISSUES:

      -  Cash offer eliminates opportunity to participate fully in potential 
         future up-side

                                                      WASSERSTEIN PERELLA & CO.
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MYCOGEN CORPORATION                                      STRATEGIC ALTERNATIVES
- -------------------------------------------------------------------------------
POTENTIAL BUSINESS STRATEGIES

OPTION II

II.   IF UNABLE TO REACH AGREEMENT ON PRICE, NEGOTIATE A SUBSTANTIAL 
      REDUCTION IN DOW'S MYCOGEN SHAREHOLDINGS.
      EXAMPLE:
      As a major agchem company, Dow's business interests have led Mycogen to 
      focus on product development for row crops such as corn, soybeans, and 
      possibly cotton. These hypercompetitive sectors are not areas which 
      Mycogen would target as an independent entity. Therefore it may be 
      possible for Mycogen to redeem a substantial portion of Dow's 
      shareholdings in the Company for a transfer to Dow of its corn and 
      soybean (and possibly cotton) conventional seed and assorted biotech 
      trait capabilities.
      BENEFITS:
      -  If a buyout not possible, then an asset separation is preferable to 
         a continuation of status-quo
      -  Grants Mycogen freedom to develop its own strategy and to pursue a 
         broader array of external collaborations.
      -  Allows Dow to capture full ownership of its most desired Mycogen 
         assets with no further cash outlay
      -  Patent defense litigation expenses follow seed assets to Dow.
      ISSUES:
      -  Taxable transaction for Mycogen with potentially significant 
         liability for capital gains.
      -  Dow unlikely to fully exit and residual shareholding (probably - 
         20%) may discourage new investments from other strategic partners.
      -  Niche strategy for Mycogen implies distant profit outlook. Priority 
         focus on row crops has delayed innovation efforts in other agro 
         sectors. WP & Co. model shows relatively low NPV for Mycogen peanut, 
         sunflower, vegetable and cereal applications.
      -  Segregation of new crop assets (i.e., breeding stations, trait 
         developments, etc.) may be problematic.
      -  Requires simultaneous recapitalization of Company to finance its 
         long term growth. Issue of new shares at attractive value in 
         secondary offering should be possible given ongoing public interest 
         in agbiotech.

                                                      WASSERSTEIN PERELLA & CO.
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MYCOGEN CORPORATION                                       STRATEGIC ALTERNATIVES
- --------------------------------------------------------------------------------
POTENTIAL BUSINESS STRATEGIES

OPTION III

III. IF DOW IS UNWILLING TO SUBSTANTIALLY CHANGE ITS SHAREHOLDING IN MYCOGEN, 
SECURE A THIRD PARTY INVESTMENT IN MYCOGEN WHICH BRINGS COMPLEMENTARY 
TECHNOLOGY AND NON-COMPETITIVE BUSINESS INTERESTS TO DOW.

     EXAMPLE:

     - Although supported by Dow Agro Sciences, the primary initiative for 
       Dow's buyout of Mycogen's public shareholders appears to be coming 
       from Dow corporate offices in Midland, Michigan. Dow Corporate's 
       interests in agbiotech may be driven by industrial feedstock 
       applications with crop protection and crop quality enhancements seen 
       as secondary benefits. As a result, it may be possible to find a 
       complimentary strategic partner who is focused on the crop aspects of 
       agbiotech but who also has assets or intellectual property which could 
       accelerate or improve the probability of success of agbiotech in 
       industrial applications.

     - One possible scenario is for the third party - after extensive 
       negotiations with Dow and Mycogen - to tender for the remaining public 
       shares of Mycogen and in a subsequent step to:

          i)  Merge a complimentary agbiotech asset into Mycogen for newly 
              issued shares; or

          ii) Swap a complimentary agbiotech asset with Dow for a portion of 
              its shareholdings.


                                                     WASSERSTEIN PERELLA & CO.
- -------------------------------------------------------------------------------



MYCOGEN CORPORATION                                       STRATEGIC ALTERNATIVES
- --------------------------------------------------------------------------------
POTENTIAL BUSINESS STRATEGIES

OPTION III (CONT'D)

     In either case, Dow's position is diluted to a 50% level and Mycogen 
     becomes a joint venture vehicle between two multinational companies. The 
     target ownership levels can be readily achieved by adjusting the value 
     of the third party asset which is contributed with cash or debt. Among 
     the possible candidates for this strategy include Zeneca or Novartis 
     where the contributed asset would likely be the seed activities of 
     either company.

     BENEFITS:

     - Expands the scope of Mycogen's technology base and enhances 
       competitiveness of overall effort in light of recent industry 
       consolidation.
     - Introduction of new entity into the situation may allow Mycogen to 
       realize full third party sale value for remaining public shares.

       ISSUES:
     - Third parties may be reluctant to invest resources in negotiating a 
       deal if they perceive situation as mere stalking horse for Dow buyout 
       bid.

                                                     WASSERSTEIN PERELLA & CO.
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MYCOGEN CORPORATION                                      STRATEGIC ALTERNATIVES
- -------------------------------------------------------------------------------
POTENTIAL BUSINESS STRATEGIES

OPTION IV

IV. IN THE EVENT OF A DEADLOCK, DEVELOP AND EXPEDITIOUSLY IMPLEMENT A 
    COMPREHENSIVE LONG-TERM FINANCING PLAN FOR THE COMPANY.
    EXAMPLE:
    - Given existing Dow proposal, current Mycogen share price and 
      preliminary WP & Co. valuation, value gap looks substantial and 
      stand-off a reasonable possibility. In recent past, the Company has 
      deferred developing any long-term financial plan due to Dow support and 
      influence. With any deadlock, there is a prospect for a reduction in 
      Dow contributions as well as a need for expanded funding by Company to 
      accelerate its own initiatives. Mycogen's weak balance sheet and 
      operating exposure to uncontrollable variables strongly suggest a need 
      for contingency plans.
    BENEFITS:
    - Credible back-up plan can provide useful leverage in Dow negotiations.
    - Rapid rate of agbiotech developments: M & A, litigation, '98 growing 
      season results, scientific discoveries, etc., may trigger sudden shift 
      in Dow strategy.
    - Sale of Verneuil minority interest and possible factoring of Monsanto 
      settlement can yield significant cash in relatively short time frame.

    ISSUES:
    - The ultimate solution requires an equity offering by the Company and 
      given the current investor focus on the sector it would be prudent to 
      go to market as soon as possible. Although WP & Co can formulate a 
      specific equity plan, it will be difficult to begin even preliminary 
      implementation without a resolution of the Dow situation.


                                                     WASSERSTEIN PERELLA & CO.
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                                       6



MYCOGEN CORPORATION
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                         -----------------------------------



                                     NEXT STEPS



                         -----------------------------------







                                                    WASSERSTEIN PERELLA & CO.
- -----------------------------------------------------------------------------



MYCOGEN CORPORATION                                                NEXT STEPS
- -----------------------------------------------------------------------------
OVERVIEW

- -    CONDUCT FOLLOW-UP BUSINESS AND FINANCIAL DUE DILIGENCE WITH DOW AND 
     MYCOGEN

- -    COMPLETE VALUATION ANALYSIS

- -    DEVELOP POINT OF VIEW REGARDING THE HISTORICAL RELATIONSHIP BETWEEN 
     MYCOGEN AND DOW

- -    REACH PRELIMINARY CONCLUSION AS TO THE RANGE OF FAIR VALUES

- -    PRESENT FINDINGS TO THE SPECIAL COMMITTEE

- -    FORMULATE RESPONSE TO DOW'S PROPOSAL AND SELECT APPROPRIATE ALTERNATIVE 
     TO PURSUE







                                                    WASSERSTEIN PERELLA & CO.
- -----------------------------------------------------------------------------





MYCOGEN CORPORATION
- -----------------------------------------------------------------------------







                         -----------------------------------



                                      APPENDIX



                         -----------------------------------







                                                    WASSERSTEIN PERELLA & CO.
- -----------------------------------------------------------------------------



[LETTERHEAD]

June 10, 1998

Mr. J. Pedro Reinhard
Executive Vice President and Chief Financial Officer
Mr. Brian Taylorson
The Dow Chemical Company
2030 Willard H. Dow Center
Midland, MI 48674

Dear Messrs. Reinhard and Taylorson:

As you know, we are serving as financial advisor to the Special Committee of 
the Board of Directors (the "Special Committee") of Mycogen Corporation 
("Mycogen") in connection with the proposal by Dow AgroSciences LLC 
("DAS") to amend the Exchange and Purchase Agreement dated January 15, 
1996, between Mycogen, Agrigenetics, Inc., DowElanco and United Agriseeds, 
Inc. and subsequent to such amendment to propose to acquire all of the 
outstanding shares of Mycogen not owned by DAS and its affiliates (the "DAS 
Proposal").

As an integral part of our due diligence, we would like to obtain information 
from and meet with representatives of Dow and DAS. This meeting would not be 
a negotiating session, since the Special Committee has made no determination 
as to whether to negotiate with Dow or DAS regarding the DAS Proposal. 
Instead, the meeting and the information we are requesting are an important 
part of our due diligence investigation to assist us in better understanding 
the DAS Proposal and Dow and DAS perspectives regarding both the DAS Proposal 
and Mycogen.

In light of the Mycogen Board of Directors meeting scheduled for June 25th in 
Chicago, we would propose an introductory meeting or dinner in Chicago either 
on June 24th or a meeting before or after the Board meeting on June 25th. The 
members of the Special Committee and representatives of both Wasserstein 
Perella and Altheimer & Gray would attend this meeting or dinner. While you 
will of course determine who would attend from the Dow/DAS group, we would 
think it important that a senior representative of Dow and DAS management 
participate.

The following list sets forth some of the general topic areas we would find 
it useful to cover in a discussion with you and the information it would be 
helpful to have prior to the meeting.

WE WOULD LIKE TO DISCUSS:

1.  The background of DAS investment in Mycogen.


[LETTERHEAD FOOTER]



2.  The reasons DAS wishes to acquire the public shares of Mycogen at this 
    time.

3.  The rationale for the $20.50 per share price offered by DAS, including 
    any pro forma projections or other analysis or valuations used in 
    preparing the $20.50 per share offer.

4.  The degree of historic involvement of DAS and Dow in the operations, 
    strategy and management of Mycogen.

5.  The terms and conditions of your proposal to amend Section 6.12 of the 
    Exchange and Purchase Agreement dated January 15, 1996.

    PLEASE PROVIDE:

6.  All analysis of the projected cost savings, synergies and growth 
    opportunities from combining DAS and Mycogen.

7.  Any analysis prepared regarding the effect of acquiring the public shares 
    of Mycogen, including but not limited to any analyses of the 
    accretive/dilutive effect on the financial results of Dow.

8.  Any business or strategic plans or analyses regarding Mycogen's different 
    business segments including any potential divestitures or acquisitions.

9.  Any pending acquisitions by DAS or DOW in the agricultural or 
    agricultural biotechnology industries that would impact the value of 
    Mycogen to Dow or DAS.

10. Any analysis of the strengths, weaknesses and/or the value of Mycogen's 
    intellectual property.

11. Any analysis of the agricultural biotechnology industry and Mycogen's 
    competitive position therein.

12. Any analysis of DAS' and Mycogen's projected combined research and 
    development spending.

To the extent we receive this information prior to our meeting we will 
obviously be able to be more substantive. I expect, however, we will have 
follow up questions after the meeting in any event.

Thank you very much for your assistance. If you have questions, please do not 
hesitate to call me. I look forward to meeting you and your colleagues.



                                       Sincerely yours,
                                       /s/ John Simpson

cc:  Joseph Sullivan
     The Hon. Clayton Yeuter
     Greg Polle
     Peter Taguc
     Scott Davis, Esq.
     Norman Gold, Esq.
     Peter Lieberman, Esq.



[LOGO]

[LETTERHEAD]

June 22, 1998



John Simpson
Wasserstein Perella & Co., Inc.
3 First National Plaza
Suite 5700
Chicago, IL 60602

Dear Mr. Simpson:

I am writing in response to your letter dated June 10, 1998. Representatives 
of Dow, along with representatives of Salomon Smith Barney and Mayer, Brown & 
Platt, would be pleased to meet with the Special Committee, its counsel and 
you at 8:00 a.m. Chicago time on the morning of June 15 in Chicago near 
O'Hare Airport. The group from Dow will be led by me.

At the meeting, we will be happy to discuss with you most of the matters 
raised in your letter. However, you should be aware that we consider some of 
the questions you have raised to be inappropriate for the evaluation of the 
proposal Dow made to the Mycogen Board on April 30, 1998. As such, we may not 
be able to answer these questions to your satisfaction.

In addition, we feel that a presentation to you of the details of our 
analyses would be inappropriate until negotiations begin, but we will 
describe to you some of the key elements of our analysis in addressing your 
questions.

We understand that you have asked about the possibility of DAS selling its 
69% ownership of the stock of Mycogen. You should be aware that Dow is not 
willing to have DAS sell its Mycogen stock and that your analysis of this 
situation should not assume that such a sale is possible.

We look forward to seeing you on June 25.

Yours sincerely,

/s/ Brian Taylorson
- -------------------
Brian Taylorson
Corporate Director
Mergers & Acquisitions

agh



[LOGO]

[LETTERHEAD]

June 22, 1998



Mr. John Simpson
Wasserstein Perella & Co., Inc.
3 First National Plaza
Suite 5700
Chicago, IL 60602



Dear Mr. Simpson:

Thank you for your letter of June 10, 1998. By now you should have been 
contacted by Brian Taylorson and representatives of Salomon Smith Barney to 
arrange a meeting to discuss the questions you have raised.

In view of my position as a director of Mycogen, I feel it is inappropriate 
that I attend this meeting. I have asked Brian Taylorson to lead a group 
which will include a Dow representative, as well as representatives from 
Salomon Smith Barney and Mayer, Brown & Platt.

Yours sincerely,
/s/ J.P. Reinhard
- -----------------
J.P. Reinhard
Executive Vice President and
Chief Financial Officer