Exhibit 2.4

                                 PROMISSORY NOTE


$48,000,000.00                                        Philadelphia, Pennsylvania
                                                                   April 4, 2002

                  FOR VALUE RECEIVED, PR BEAVER VALLEY LIMITED PARTNERSHIP, a
Pennsylvania limited partnership, as maker, having its principal place of
business at 200 S. Broad Street, 3rd Floor, Philadelphia, Pennsylvania 19102
("Borrower"), hereby unconditionally PROMISES AND AGREES TO PAY to the order of
COLUMN FINANCIAL, INC., as payee, having an address at 11 Madison Avenue, New
York, New York 10010 ("Lender"), or at such other place as the holder hereof may
from time to time designate in writing, the principal sum of FORTY EIGHT MILLION
AND NO/100 DOLLARS ($48,000,000.00), in lawful money of the United States of
America, with interest thereon to be computed from the date of this Note at the
Interest Rate, and to be paid in accordance with the terms of this Note and that
certain Loan Agreement, dated as of the date hereof, between Borrower and Lender
(as the same may be amended, restated, replaced, supplemented or otherwise
modified from time to time, the "Loan Agreement"). All capitalized terms not
defined herein shall have the respective meanings set forth in the Loan
Agreement.

                            ARTICLE 1: PAYMENT TERMS

                  Borrower agrees to pay the principal sum of this Note and
interest on the unpaid principal sum of this Note from time to time outstanding
at the rates and at the times specified in Article 2 of the Loan Agreement and
the outstanding balance of the principal sum of this Note and all accrued and
unpaid interest thereon shall be due and payable on the Maturity Date.

                       ARTICLE 2: DEFAULT AND ACCELERATION

                  The Debt shall without notice become immediately due and
payable at the option of Lender if any payment required in this Note is not paid
on or prior to the date when due or if not paid on the Maturity Date or on the
happening of any other Event of Default.

                            ARTICLE 3: LOAN DOCUMENTS

                  This Note is secured by the Mortgage and the other Loan
Documents. All of the terms, covenants and conditions contained in the Loan
Agreement, the Mortgage and the other Loan Documents are hereby made a part of
this Note to the same extent and with the same force as if they were fully set
forth herein. In the event of a conflict or inconsistency between the terms of
this Note and the Loan Agreement, the terms and provisions of the Loan Agreement
shall govern.

                            ARTICLE 4: SAVINGS CLAUSE

                  Notwithstanding anything to the contrary, (a) all agreements
and communications between Borrower and Lender are hereby and shall
automatically be limited so that, after taking into account all amounts deemed
interest, the interest contracted for, charged or received by Lender shall never
exceed the maximum lawful rate or amount, (b) in calculating whether any
interest exceeds the lawful maximum, all such interest shall be amortized,
prorated, allocated and spread over the full amount and term of all principal
indebtedness of Borrower to Lender, and (c) if through any contingency or event
Lender receives or is deemed to receive interest in excess of the lawful
maximum, any such excess shall be deemed to have been applied toward payment of
the principal of any and all then outstanding indebtedness of Borrower to
Lender.





                            ARTICLE 5: NO ORAL CHANGE

                  This Note may not be modified, amended, waived, extended,
changed, discharged or terminated orally or by any act or failure to act on the
part of Borrower or Lender, but only by an agreement in writing signed by the
party against whom enforcement of any modification, amendment, waiver,
extension, change, discharge or termination is sought.

                               ARTICLE 6: WAIVERS

                  Borrower and all others who may become liable for the payment
of all or any part of the Debt do hereby severally waive presentment and demand
for payment, notice of dishonor, notice of intention to accelerate, notice of
acceleration, protest and notice of protest and non-payment and all other
notices of any kind. No release of any security for the Debt or extension of
time for payment of this Note or any installment hereof, and no alteration,
amendment or waiver of any provision of this Note, the Loan Agreement or the
other Loan Documents made by agreement between Lender or any other Person shall
release, modify, amend, waive, extend, change, discharge, terminate or affect
the liability of Borrower, or any other Person who may become liable for the
payment of all or any part of the Debt, under this Note, the Loan Agreement or
the other Loan Documents. No notice to or demand on Borrower shall be deemed to
be a waiver of the obligation of Borrower or of the right of Lender to take
further action without further notice or demand as provided for in this Note,
the Loan Agreement or the other Loan Documents. If Borrower is a partnership,
the agreements herein contained shall remain in full force and be applicable,
notwithstanding any changes in the individuals or entities comprising the
partnership, and the term "Borrower," as used herein, shall include any
alternate or successor partnership, but any predecessor partnership and their
partners shall not thereby be released from any liability. If Borrower is a
corporation, the agreements contained herein shall remain in full force and be
applicable notwithstanding any changes in the shareholders comprising, or the
officers and directors relating to, the corporation, and the term "Borrower", as
used herein, shall include any alternative or successor corporation, but any
predecessor corporation shall not be relieved of liability hereunder. If
Borrower is a limited liability company, the agreements herein contained shall
remain in full force and be applicable, notwithstanding any changes in the
members comprising the limited liability company, and the term "Borrower", as
used herein, shall include any alternate or successor limited liability company,
but any predecessor limited liability company and their members shall not
thereby be released from any liability. (Nothing in the foregoing sentence shall
be construed as a consent to, or a waiver of, any prohibition or restriction on
transfers of interests in such partnership, corporation or limited liability
company which may be set forth in the Loan Agreement, the Mortgage or any other
Loan Document.)

                               ARTICLE 7: TRANSFER

                  Upon the transfer of this Note, Borrower hereby waiving notice
of any such transfer, Lender may deliver all the collateral mortgaged, granted,
pledged or assigned pursuant to the Loan Documents, or any part thereof, to the
transferee who shall thereupon become vested with all the rights herein or under
applicable law given to Lender with respect thereto, and Lender shall thereafter
forever be relieved and fully discharged from any liability or responsibility in
the matter; but Lender shall retain all rights hereby given to it with respect
to any liabilities and the collateral not so transferred.




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                             ARTICLE 8: EXCULPATION

                  The provisions of Section 9.4 of the Loan Agreement are hereby
incorporated by reference into this Note to the same extent and with the same
force as if fully set forth herein.

                            ARTICLE 9: GOVERNING LAW

                  This Note shall be governed in accordance with the terms and
provisions of Section 10.3 of the Loan Agreement.

                               ARTICLE 10: NOTICES

                  All notices or other written communications hereunder shall be
delivered in accordance with Section 10.6 of the Loan Agreement.


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                  IN WITNESS WHEREOF, Borrower has duly executed this Promissory
Note as of the day and year first above written.

                             PR BEAVER VALLEY LIMITED PARTNERSHIP,
                             a Pennsylvania limited partnership

                             By:  PR Beaver Valley LLC,
                                  a Delaware limited liability company,
                                  its sole general partner

                                  By:  PREIT Associates, L.P.,
                                       a Delaware limited partnership,
                                       its sole member

                                       By:  Pennsylvania Real Estate
                                            Investment Trust,
                                            a Pennsylvania business trust,
                                            its general partner


                                            By: /s/ Jeffrey A. Linn
                                                --------------------------------
                                                Name:  Jeffrey A. Linn
                                                Title: Executive Vice President