Exhibit 12

                                  ENDOGEN, INC.

                                 1992 STOCK PLAN



         1. PURPOSE. This 1992 Stock Plan (the "Plan") is an amendment and
restatement of the 1989 Stock Plan of Endogen, Inc. (the "Company") and is
intended to provide incentives: (a) to the officers and other employees of the
Company, its parent (if any) and any present or future subsidiaries of the
Company (collectively, "Related Corporations") by providing them with
opportunities to purchase stock in the Company pursuant to options granted
hereunder which qualify as "incentive stock options" under Section 422(b) of the
Internal Revenue Code of 1986, as amended (the "Code") ("ISO" or "ISOs"); (b) to
directors, officers, employees and consultants of the Company and Related
Corporations by providing them with opportunities to purchase stock in the
Company pursuant to options granted hereunder which do not qualify as ISOs
("Non-Qualified Option" or "Non-Qualified Options"); (c) to directors, officers,
employees and consultants of the Company and Related Corporations by providing
them with awards of stock in the Company ("Awards"); and (d) to directors,
officers, employees and consultants of the Company and Related Corporations by
providing them with opportunities to make direct purchases of stock in the
Company ("Purchases"). Both ISOs and Non-Qualified Options are referred to
hereafter individually as an "Option" and collectively as "Options". Options,
Awards and authorizations to make Purchases are referred to hereafter
collectively as "Stock Rights". As used herein, the terms "parent" and
"subsidiary" mean "parent corporation" and "subsidiary corporation",
respectively, as those terms are defined in Section 424 of the Code.

         2.       ADMINISTRATION OF THE PLAN.

         A. BOARD OR COMMITTEE ADMINISTRATION. The Plan shall be administered by
      the Board of Directors of the Company (the "Board") or, subject to
      paragraph 2(D) (relating to compliance with Section 162(m) of the Code),
      by a committee appointed by the Board (the "Committee"); provided, that,
      to the extent required by Rule 16b-3, or any successor provision ("Rule
      16b-3"), of the Securities Exchange Act of 1934, with respect to specific
      grants of Stock Rights, the Plan shall be administered by a disinterested
      administrator or administrators within the meaning of Rule 16b-3.
      Hereinafter, all references in this Plan to the "Committee" shall mean the
      Board if no Committee has been appointed. Subject to ratification of the
      grant or authorization of each Stock Right by the Board (if so required by
      applicable state law), and subject to the terms of the Plan, the Committee
      shall have the authority to (i) determine the employees of the Company and
      Related Corporations (from among the class of employees eligible under
      paragraph 3 to receive ISOs) to whom ISOs may be granted, and to determine
      (from among the class of individuals and entities eligible under paragraph
      3 to receive Non-Qualified Options and Awards and to make Purchases) to
      whom Non-Qualified Options, Awards and authorizations to make Purchases
      may be granted; (ii) determine the time or times at which Options or
      Awards may be granted or Purchases made; (iii) determine the option price
      of shares subject to each Option, which



                                       -2-

      price shall not be less than the minimum price specified in paragraph 6,
      and the purchase price of shares subject to each Purchase; (iv) determine
      whether each Option granted shall be an ISO or a Non-Qualified Option;
      (v) determine (subject to paragraphs 7 and 9) the time or times when each
      Option shall become exercisable and the duration of the exercise period;
      (vi) determine whether restrictions such as repurchase options are to be
      imposed on shares subject to Options, Awards and Purchases and the nature
      of such restrictions, if any, and (vii) interpret the Plan and prescribe
      and rescind rules and regulations relating to it. If the Committee
      determines to issue a Non-Qualified Option, it shall take whatever actions
      it deems necessary, under Section 422 of the Code and the regulations
      promulgated thereunder, to ensure that such Option is not treated as an
      ISO. The interpretation and construction by the Committee of any
      provisions of the Plan or of any Stock Right granted under it shall be
      final unless otherwise determined by the Board. The Committee may from
      time to time adopt such rules and regulations for carrying out the Plan as
      it may deem best. No member of the Board or the Committee shall be liable
      for any action or determination made in good faith with respect to the
      Plan or any Stock Right granted under it.

         B. COMMITTEE ACTIONS. The Committee may select one of its members as
      its chairman, and shall hold meetings at such times and places as it may
      determine. Acts by a majority of the Committee, or acts reduced to or
      approved in writing by a majority of the members of the Committee (if
      consistent with applicable state law), shall be the valid acts of the
      Committee. From time to time the Board may increase the size of the
      Committee and appoint additional members thereof, remove members (with or
      without cause) and appoint new members in substitution therefor, fill
      vacancies however caused, or remove all members of the Committee and
      thereafter directly administer the Plan.

         C. GRANT OF STOCK RIGHTS TO BOARD MEMBERS. Stock Rights may be granted
      to members of the Board consistent with the provisions of the first
      sentence of paragraph 2(A) above, if applicable. All grants of Stock
      Rights to members of the Board shall in all other respects be made in
      accordance with the provisions of this Plan applicable to other eligible
      persons. Members of the Board who are either (i) eligible for Stock Rights
      pursuant to the Plan or (ii) have been granted Stock Rights may vote on
      any matters affecting the administration of the Plan or the grant of any
      Stock Rights pursuant to the Plan, except that no such member shall act
      upon the granting to himself of Stock Rights, but any such member may be
      counted in determining the existence of a quorum at any meeting of the
      Board during which action is taken with respect to the granting to him of
      Stock Rights.

         D. PERFORMANCE-BASED COMPENSATION. The Board, in its discretion, may
      take such action as may be necessary to ensure that Stock Rights
      granted under the Plan qualify as "qualified performance-based
      compensation" within the meaning of Section 162(m) of the Code and
      applicable regulations promulgated thereunder ("Performance-Based
      Compensation"). Such action may include, in the Board's discretion,
      some or all of the following (i) if the Board determines that Stock
      Rights granted under the Plan generally shall constitute
      Performance-Based Compensation, the Plan shall be administered, to the
      extent required for such Stock Rights to constitute Performance-Based
      Compensation, by a Committee consisting solely of two or more "outside
      directors" (as defined in applicable regulations promulgated under
      Section 162(m) of the Code), (ii) if any Non-Qualified



                                      -3-

      Options with an exercise price less than the fair market value per share
      of Common Stock are granted under the Plan and the Board determines that
      such Options should constitute Performance-Based Compensation, such
      options shall be made exercisable only upon the attainment of a
      pre-established, objective performance goal established by the Committee,
      and such grant shall be submitted for, and shall be contingent upon
      shareholder approval and (iii) Stock Rights granted under the Plan may be
      subject to such other terms and conditions as are necessary for
      compensation recognized in connection with the exercise or disposition of
      such Stock Right or the disposition of Common Stock acquired pursuant to
      such Stock Right, to constitute Performance-Based Compensation.

         3. ELIGIBLE EMPLOYEES AND OTHERS. ISOs may be granted to any employee
of the Company or any Related Corporation. Those officers and directors of the
Company who are not employees may not be granted ISOs under the Plan.
Non-Qualified Options, Awards and authorizations to make Purchases may be
granted to any employee, officer or director (whether or not also an employee)
or consultant of the Company or any Related Corporation. The Committee may take
into consideration a recipient's individual circumstances in determining whether
to grant an ISO, a Non-Qualified Option, an Award or an authorization to make a
Purchase. Granting of any Stock Right to any individual or entity shall neither
entitle that individual or entity to, nor disqualify him from, participation in
any other grant of Stock Rights.

         4. STOCK. The stock subject to Options, Awards and Purchases shall be
authorized but unissued shares of Common Stock of the Company, par value $.01
per share (the "Common Stock"), or shares of Common Stock reacquired by the
Company in any manner. The aggregate number of shares which may be issued
pursuant to the Plan is 1,250,000, subject to adjustment as provided in
paragraph 13. Any such shares may be issued pursuant to any type of Stock Rights
granted under the Plan, so long as the number of shares so issued does not
exceed such number, as adjusted. If any Stock Right granted under the Plan shall
expire or terminate for any reason without having been exercised in full or
shall cease for any reason to be exercisable in whole or in part, the
unpurchased shares subject to such Stock Right shall again be available for
grants of Stock Rights under the Plan.

                   No employee of the Company or any Related Corporation may be
granted Stock Rights to acquire, in the aggregate, more than 200,000 shares of
Common Stock under the Plan during any fiscal year of the Company. If any Stock
Right granted under the Plan shall expire or terminate for any reason without
having been exercised in full or shall cease for any reason to be exercisable in
whole or in part or shall be repurchased by the Company, the shares subject to
such Stock Right shall be included in the determination of the aggregate number
of shares of Common Stock deemed to have been granted to such employee under the
Plan.


         5. GRANTING OF STOCK RIGHTS. Stock Rights may be granted under the Plan
at any time after August 10, 1992 and prior to August 9, 2002. The date of grant
of a Stock Right under the Plan will be the date specified by the Committee at
the time it grants the Stock Right; provided, however, that such date shall not
be prior to the date on which the Committee acts to approve the grant. The
Committee shall have the right, with the consent of the optionee, to convert an
ISO granted under the Plan to a Non-Qualified Option pursuant to paragraph 16.



                                      -4-

         6.       MINIMUM OPTION PRICE; ISO LIMITATIONS.

         A. PRICE FOR NON-QUALIFIED OPTIONS. Subject to paragraph 2(D) (relating
      to compliance with Section 162(m) of the Code), the exercise price per
      share specified in the agreement relating to each Non-Qualified Option
      granted under the Plan shall in no event be less than the minimum legal
      consideration required therefor under the laws of the Commonwealth of
      Massachusetts or the laws of any jurisdiction in which the Company or its
      successors in interest may be organized.

         B. PRICE FOR ISOS. The exercise price per share specified in the
      agreement relating to each ISO granted under the Plan shall not be less
      than the fair market value per share of Common Stock on the date of such
      grant. In the case of an ISO to be granted to an employee owning stock
      possessing more than ten percent (10%) of the total combined voting power
      of all classes of stock of the Company or any Related Corporation, the
      price per share specified in the agreement relating to such ISO shall not
      be less than one hundred ten percent (110%) of the fair market value per
      share of Common Stock on the date of grant. For purposes of determining
      stock ownership under this paragraph, the rules of Section 424(d) of the
      Code shall apply.

         C. $100,000 ANNUAL LIMITATION ON ISO VESTING. Each eligible employee
      may be granted Options treated as ISOs only to the extent that, in the
      aggregate under this Plan and all incentive stock option plans of the
      Company and any Related Corporation, ISOs do not become exercisable for
      the first time by such employee during any calendar year with respect to
      stock having a fair market value (determined at the time the ISOs were
      granted) in excess of $100,000. The Company intends to designate any
      Options granted in excess of such limitation as Non-Qualified Options.

         D. DETERMINATION OF FAIR MARKET VALUE. If, at the time an Option is
      granted under the Plan, the Company's Common Stock is publicly traded,
      "fair market value" shall be determined as of the last business day for
      which the prices or quotes discussed in this sentence are available prior
      to the date such Option is granted and shall mean (i) the average (on that
      date) of the high and low prices of the Common Stock on the principal
      national securities exchange on which the Common Stock is traded, if the
      Common Stock is then traded on a national securities exchange; or (ii) the
      last reported sale price (on that date) of the Common Stock on the Nasdaq
      National Market List, if the Common Stock is not then traded on a national
      securities exchange; or (iii) the closing bid price (or average of bid
      prices) last quoted (on that date) by an established quotation service for
      over-the-counter securities, if the Common Stock is not reported on the
      Nasdaq National Market List. However, if the Common Stock is not publicly
      traded at the time an Option is granted under the Plan, "fair market
      value" shall be deemed to be the fair value of the Common Stock as
      determined by the Committee after taking into consideration all factors
      which it deems appropriate, including, without limitation, recent sale and
      offer prices of the Common Stock in private transactions negotiated at
      arm's length.



                                      -5-

         7. OPTION DURATION. Subject to earlier termination as provided in
paragraphs 9 and 10, each Option shall expire on the date specified by the
Committee, but not more than (i) ten years and one day from the date of grant in
the case of Non-Qualified Options, (ii) ten years from the date of grant in the
case of ISOs generally, and (iii) five years from the date of grant in the case
of ISOs granted to an employee owning stock possessing more than ten percent
(10%) of the total combined voting power of all classes of stock of the Company
or any Related Corporation, as determined under paragraph 6(B). Subject to
earlier termination as provided in paragraphs 9 and 10, the term of each ISO
shall be the term set forth in the original instrument granting such ISO, except
with respect to any part of such ISO that is converted into a Non-Qualified
Option pursuant to paragraph 16.

         8. EXERCISE OF OPTION. Subject to the provisions of paragraphs 9
through 12, each Option granted under the Plan shall be exercisable as follows:

         A. VESTING. The Option shall either be fully exercisable on the date
       of grant or shall become exercisable thereafter in such installments
       as the Committee may specify.

         B. FULL VESTING OF INSTALLMENTS. Once an installment becomes
       exercisable it shall remain exercisable until expiration or
       termination of the Option, unless otherwise specified by the Committee.

         C. PARTIAL EXERCISE. Each Option or installment may be exercised at
       any time or from time to time, in whole or in part, for up to the
       total number of shares with respect to which it is then exercisable.

         D. ACCELERATION OF VESTING. The Committee shall have the right to
       accelerate the date of exercise of any installment of any Option;
       provided that the Committee shall not, without the consent of an
       optionee, accelerate the exercise date of any installment of any
       Option granted to any employee as an ISO (and not previously converted
       into a Non-Qualified Option pursuant to paragraph 16) if such
       acceleration would violate the annual vesting limitation contained in
       Section 422(d) of the Code, as described in paragraph 6(C).

         9. TERMINATION OF EMPLOYMENT. If an ISO optionee ceases to be employed
by the Company and all Related Corporations other than by reason of death or
disability as defined in paragraph 10, no further installments of his ISOs shall
become exercisable, and his ISOs shall terminate after the passage of ninety
(90) days from the date of termination of his employment, but in no event later
than on their specified expiration dates, except to the extent that such ISOs
(or unexercised installments thereof) have been converted into Non-Qualified
Options pursuant to paragraph 16. For purposes of this paragraph 9 only,
employment shall be considered as continuing uninterrupted during any bona fide
leave of absence (such as those attributable to illness, military obligations or
governmental service) provided that the period of such leave does not exceed 90
days or, if longer, any period during which such optionee's right to
re-employment is guaranteed by statute. A bona fide leave of absence with the
written approval of the Committee shall not be considered an interruption of
employment under this paragraph 9, provided that such written approval
contractually obligates the Company or any Related Corporation to continue the
employment of the optionee after the approved period of absence.



                                      -6-

ISOs granted under the Plan shall not be affected by any change of employment
within or among the Company and Related Corporations, so long as the optionee
continues to be an employee of the Company or any Related Corporation. Nothing
in the Plan shall be deemed to give any grantee of any Stock Right the right to
be retained in employment or other service by the Company or any Related
Corporation for any period of time.

         10. DEATH; DISABILITY.

         A. DEATH. If an ISO optionee ceases to be employed by the Company and
      all Related Corporations by reason of his death, any ISO of his may be
      exercised, to the extent of the number of shares with respect to which he
      could have exercised it on the date of his death, by his estate, personal
      representative or beneficiary who has acquired the ISO by will or by the
      laws of descent and distribution, at any time prior to the earlier of the
      specified expiration date of the ISO or 180 days from the date of the
      optionee's death.

         B. DISABILITY. If an ISO optionee ceases to be employed by the Company
      and all Related Corporations by reason of his disability, he shall have
      the right to exercise any ISO held by him on the date of termination of
      employment, to the extent of the number of shares with respect to which he
      could have exercised it on that date, at any time prior to the earlier of
      the specified expiration date of the ISO or 180 days from the date of the
      termination of the optionee's employment. For the purposes of the Plan,
      the term "disability" shall mean "permanent and total disability" as
      defined in Section 22(e)(3) of the Code or successor statute.

         11. ASSIGNABILITY. No Stock Right shall be assignable or transferable
by the grantee except by will or by the laws of descent and distribution. During
the lifetime of the grantee each Stock Right shall be exercisable only by him.

         12. TERMS AND CONDITIONS OF OPTIONS. Options shall be evidenced by
instruments (which need not be identical) in such forms as the Committee may
from time to time approve. Such instruments shall conform to the terms and
conditions set forth in paragraphs 6 through 11 hereof and may contain such
other provisions as the Committee deems advisable which are not inconsistent
with the Plan, including restrictions applicable to shares of Common Stock
issuable upon exercise of Options. In granting any Non-Qualified Option, the
Committee may specify that such Non-Qualified Option shall be subject to the
restrictions set forth herein with respect to ISOs, or to such other termination
and cancellation provisions as the Committee may determine. The Committee may
from time to time confer authority and responsibility on one or more of its own
members and/or one or more officers of the Company to execute and deliver such
instruments. The proper officers of the Company are authorized and directed to
take any and all action necessary or advisable from time to time to carry out
the terms of such instruments.

         13. ADJUSTMENTS. Upon the occurrence of any of the following events, an
optionee's rights with respect to Options granted to him hereunder shall be
adjusted as hereinafter provided, unless otherwise specifically provided in the
written agreement between the optionee and the Company relating to such Option:



                                      -7-

         A. STOCK DIVIDENDS AND STOCK SPLITS. If the shares of Common Stock
      shall be subdivided or combined into a greater or smaller number of shares
      or if the Company shall issue any shares of Common Stock as a stock
      dividend on its outstanding Common Stock, the number of shares of Common
      Stock deliverable upon the exercise of Options shall be appropriately
      increased or decreased proportionately, and appropriate adjustments shall
      be made in the purchase price per share to reflect such subdivision,
      combination or stock dividend.

         B. CONSOLIDATIONS OR MERGERS. If the Company is to be consolidated with
      or acquired by another entity in a merger, sale of all or substantially
      all of the Company's assets or otherwise (an "Acquisition"), the Committee
      or the board of directors of any entity assuming the obligations of the
      Company hereunder (the "Successor Board"), shall, as to outstanding
      Options, either (i) make appropriate provision for the continuation of
      such Options by substituting on an equitable basis for the shares then
      subject to such Options the consideration payable with respect to the
      outstanding shares of Common Stock in connection with the Acquisition; or
      (ii) upon written notice to the optionees, provide that all Options must
      be exercised, to the extent then exercisable, within a specified number of
      days of the date of such notice, at the end of which period the Options
      shall terminate; or (iii) terminate all Options in exchange for a cash
      payment equal to the excess of the fair market value of the shares subject
      to such Options (to the extent then exercisable) over the exercise price
      thereof.

         C. RECAPITALIZATION OR REORGANIZATION. In the event of a
      recapitalization or reorganization of the Company (other than a
      transaction described in subparagraph B above) pursuant to which
      securities of the Company or of another corporation are issued with
      respect to the outstanding shares of Common Stock, an optionee upon
      exercising an Option shall be entitled to receive for the purchase price
      paid upon such exercise the securities he would have received if he had
      exercised his Option prior to such recapitalization or reorganization.

         D. MODIFICATION OF ISOS. Notwithstanding the foregoing, any adjustments
      made pursuant to subparagraphs A, B or C with respect to ISOs shall be
      made only after the Committee, after consulting with counsel for the
      Company, determines whether such adjustments would constitute a
      "modification" of such ISOs (as that term is defined in Section 424 of the
      Code) or would cause any adverse tax consequences for the holders of such
      ISOs. If the Committee determines that such adjustments made with respect
      to ISOs would constitute a modification of such ISOs, it may refrain from
      making such adjustments.

         E. DISSOLUTION OR LIQUIDATION. In the event of the proposed dissolution
      or liquidation of the Company, each Option will terminate immediately
      prior to the consummation of such proposed action or at such other time
      and subject to such other conditions as shall be determined by the
      Committee.

         F. ISSUANCES OF SECURITIES. Except as expressly provided herein, no
      issuance by the Company of shares of stock of any class, or securities
      convertible into shares of stock of any class, shall affect, and no
      adjustment by reason thereof shall be made with respect to, the



                                      -8-

       number or price of shares subject to Options. No adjustments shall be
       made for dividends paid in cash or in property other than securities of
       the Company.

         G. FRACTIONAL SHARES. No fractional shares shall be issued under the
      Plan and the optionee shall receive from the Company cash in lieu of such
      fractional shares.

         H. ADJUSTMENTS. Upon the happening of any of the events described in
      subparagraphs A, B or C above, the class and aggregate number of shares
      set forth in paragraph 4 hereof that are subject to Stock Rights which
      previously have been or subsequently may be granted under the Plan shall
      also be appropriately adjusted to reflect the events described in such
      subparagraphs. The Committee or the Successor Board shall determine the
      specific adjustments to be made under this paragraph 13 and, subject to
      paragraph 2, its determination shall be conclusive.

         If any person or entity owning restricted Common Stock obtained by
exercise of a Stock Right made hereunder receives shares or securities or cash
in connection with a corporate transaction described in subparagraphs A, B or C
above as a result of owning such restricted Common Stock, such shares or
securities or cash shall be subject to all of the conditions and restrictions
applicable to the restricted Common Stock with respect to which such shares or
securities or cash were issued, unless otherwise determined by the Committee or
the Successor Board.

         14. MEANS OF EXERCISING STOCK RIGHTS. A Stock Right (or any part or
installment thereof) shall be exercised by giving written notice to the Company
at its principal office address. Such notice shall identify the Stock Right
being exercised and specify the number of shares as to which such Stock Right is
being exercised, accompanied by full payment of the purchase price therefor
either (a) in United States dollars in cash or by check, or (b) at the
discretion of the Committee, through delivery of shares of Common Stock having a
fair market value equal as of the date of the exercise to the cash exercise
price of the Stock Right, (c) at the discretion of the Committee, by delivery of
the grantee's personal recourse note bearing interest payable not less than
annually at no less than 100% of the lowest applicable Federal rate, as defined
in Section 1274(d) of the Code, (d) at the discretion of the Committee and
consistent with applicable law, through the delivery of an assignment to the
Company of a sufficient amount of the proceeds from the sale of the Common Stock
acquired upon exercise of the Stock Right and an authorization to the broker or
selling agent to pay that amount to the Company, which sale shall be at the
participant's direction at the time of exercise, or (e) at the discretion of the
Committee, by any combination of (a), (b), (c) and (d) above. If the Committee
exercises its discretion to permit payment of the exercise price of an ISO by
means of the methods set forth in clauses (b), (c), (d) or (e) of the preceding
sentence, such discretion shall be exercised in writing at the time of the grant
of the ISO in question. The holder of a Stock Right shall not have the rights of
a shareholder with respect to the shares covered by his Stock Right until the
date of issuance of a stock certificate to him for such shares. Except as
expressly provided above in paragraph 13 with respect to changes in
capitalization and stock dividends, no adjustment shall be made for dividends or
similar rights for which the record date is before the date such stock
certificate is issued.



                                      -9-

         15. TERM AND AMENDMENT OF PLAN. This Plan was adopted by the Board of
Directors of the Company on August 10, 1992, subject to approval of the Plan by
the stockholders of the Company. The Plan shall expire at the end of the day on
August 9, 2002 (except as to Options outstanding on that date). The Board may
terminate or amend the Plan in any respect at any time, except that, without the
approval of the stockholders obtained within 12 months before or after the Board
adopts a resolution authorizing any of the following actions: (a) the total
number of shares that may be issued under the Plan may not materially be
increased (except by adjustment pursuant to paragraph 13); (b) the benefits
accruing to participants under the Plan may not materially be increased; (c) the
requirements as to eligibility to participate in the Plan may not materially be
modified; (d) the provisions of paragraph 3 regarding eligibility for grants of
ISOs may not be modified; (e) the provisions of paragraph 6(B) regarding the
exercise price at which shares may be offered pursuant to ISOs may not be
modified (except by adjustment pursuant to paragraph 13); and (f) the expiration
date of the Plan may not be extended. Except as otherwise provided in this
paragraph 15, in no event may action of the Board or stockholders alter or
impair the rights of a grantee, without his consent, under any Stock Right
previously granted to him.

         16. CONVERSION OF ISOs INTO NON-QUALIFIED OPTIONS; TERMINATION OF ISOs.
The Committee, at the written request of any optionee, may in its discretion
take such actions as may be necessary to convert such optionee's ISOs (or any
installments or portions of installments thereof) that have not been exercised
on the date of conversion into Non-Qualified Options at any time prior to the
expiration of such ISOs, regardless of whether the optionee is an employee of
the Company or a Related Corporation at the time of such conversion. Such
actions may include, but shall not be limited to, extending the exercise period
or reducing the exercise price of the appropriate installments of such ISOs. At
the time of such conversion, the Committee (with the consent of the optionee)
may impose such conditions on the exercise of the resulting Non-Qualified
Options as the Committee in its discretion may determine, provided that such
conditions shall not be inconsistent with this Plan. Nothing in the Plan shall
be deemed to give any optionee the right to have such optionee's ISOs converted
into Non-Qualified Options, and no such conversion shall occur until and unless
the Committee takes appropriate action. The Committee, with the consent of the
optionee, may also terminate any portion of any ISO that has not been exercised
at the time of such termination.

         17. APPLICATION OF FUNDS. The proceeds received by the Company from the
sale of shares pursuant to Options granted and Purchases authorized under the
Plan shall be used for general corporate purposes.

         18. NOTICE TO COMPANY OF DISQUALIFYING DISPOSITION. By accepting an ISO
granted under the Plan, each optionee agrees to notify the Company in writing
immediately after he/she (or any transferee to whom Section 424(c)(4) of the
Code, relating to transfers to a spouse or former spouse, applies) makes a
Disqualifying Disposition, as described in Sections 421, 422 and 424 of the Code
and regulations thereunder, of any stock acquired under the Plan (or stock or
securities received in a transaction described in Section 424(b) or 424(c)(1)(B)
of the Code, relating to distributions of stock with respect to stock acquired
under the Plan and certain tax-free exchanges of stock acquired under the Plan
for other stock or securities). A Disqualifying Disposition (with certain
exceptions) is generally any disposition within two years of the date the



                                      -10-

ISO was granted or within one year of the date the ISO was exercised, whichever
period ends later. With respect to stock or securities held jointly with right
of survivorship, a termination of such joint tenancy may constitute a
Disqualifying Disposition. This paragraph 18 shall be made binding upon the
optionee and upon any transferee of stock or securities described in this
paragraph to whom Section 424(c)(4) of the Code applies.

         19. WITHHOLDING OF ADDITIONAL INCOME TAXES. Upon the exercise of a
Non-Qualified Option, the grant of an Award, the making of a Purchase of Common
Stock for less than its fair market value, the making of a Disqualifying
Disposition (as defined in paragraph 18), the vesting or transfer of restricted
stock acquired on the exercise of a Stock Right hereunder (or stock or
securities received in a transaction described in Section 424(b) or 424(c)(1)(B)
of the Code), or the making of a distribution or other payment with respect to
such stock or securities, the Company may withhold taxes in respect of amounts
that constitute compensation includible in gross income, whenever the Company
determines that such withholding is required. The Committee in its discretion
may condition (i) the exercise of an Option, (ii) the grant of an Award, (iii)
the making of a Purchase of Common Stock for less than its fair market value, or
(iv) the vesting of restricted Common Stock acquired by exercising a Stock
Right, on the grantee's making satisfactory arrangement for such withholding.

         20. GOVERNMENTAL REGULATION. The Company's obligation to sell and
deliver shares of the Common Stock under this Plan is subject to the approval of
any governmental authority required in connection with the authorization,
issuance or sale of such shares.

         In addition to tax withholding, government regulations may impose
reporting or other obligations on the Company with respect to the Plan. For
example, the Company may be required to send tax information statements to
employees and former employees that exercise ISOs.

         21. COMPLIANCE WITH REGULATIONS. It is the Company's intent that the
Plan comply in all respects with Rule 16b-3 and any applicable Securities and
Exchange Commission interpretations thereof. If any provision of this Plan is
deemed not to be in compliance with Rule 16b-3, the provisions shall be null and
void.

         22. GOVERNING LAW; CONSTRUCTION. The validity and construction of the
Plan and the instruments evidencing Stock Rights shall be governed by the laws
of the Commonwealth of Massachusetts, or the laws of any jurisdiction in which
the Company or its successors in interest may be organized. In construing this
Plan, the singular shall include the plural and the masculine gender shall
include the feminine and neuter, unless the context otherwise requires.