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                                                                   EXHIBIT 10.46

                              ASSUMPTION AGREEMENT

      This assumption agreement (this "Agreement") is made and entered into this
19th day of October, 2004 by and between General Growth Properties, Inc., a
Delaware corporation ("GGP"), and The Rouse Company, a Maryland corporation
("Rouse") in favor of and for the benefit of the Holders and the Representatives
referred to below.

      WHEREAS, GGP, Rouse and Red Acquisition LLPC ("Merger Sub") are parties to
that certain Agreement and Plan of Merger dated as of August 19, 2004 (the "2004
Merger Agreement") providing for the merger of Merger Sub with and into Rouse
(the "2004 Merger"), with Rouse as the surviving corporation in such merger.

      WHEREAS, in 1996 Rouse acquired The Hughes Corporation ("THC") pursuant to
that certain Agreement and Plan of Merger, dated as of February 22, 1996 (the
"1996 Merger Agreement"), among Rouse, TRC Acquisition Company I and THC.

      WHEREAS, in satisfaction of a condition precedent set forth in the 1996
Merger Agreement, Rouse entered into that certain Contingent Stock Agreement,
effective as of January 1, 1996 (as it has been or may be amended in accordance
with its terms, the "CSA"), in favor of and for the benefit of the Holders and
the Representatives (as such terms are defined in the CSA).

      Whereas, pursuant to Section 7.04(a) of the CSA, Rouse agreed to require
any successor to all or substantially all of the business and/or assets of Rouse
to expressly assume and agree to perform the CSA in the same manner and to the
same extent that Rouse would be required to perform it if no succession took
place.

      NOW, THEREFORE, GGP hereby covenants and agrees as follows:

      1.    As of the Effective Time (as defined in the 2004 Merger Agreement),
            GGP, as successor to Rouse, hereby expressly assumes, agrees to be
            bound by and agrees to perform the CSA in the same manner and to the
            same extent that Rouse would be bound by and required to perform the
            CSA had the 2004 Merger not taken place. It is specifically
            understood and agreed that the foregoing assumption by and covenant
            of GGP applies to all rights, covenants, liabilities and obligations
            whatsoever arising under the CSA, whether arising before or after
            the Effective Time and whether known or unknown, fixed or
            contingent, in each case to the same extent as would be applicable
            to Rouse has the 2004 Merger not taken place and including, without
            limitation, any obligation to deliver Contingent Shares (as defined
            in the CSA) in respect of Calculation Dates (as defined in the CSA)
            occurring prior to the 2004 Merger.

      2.    Pursuant to paragraph 1 above and in furtherance of the satisfaction
            of the requirements of Section 7.04(b) of the CSA, GGP agrees that
            following the Effective Time (a) there will not be a prejudicial
            effect on the Holders with respect to their non-taxable receipt of
            securities pursuant to the CSA as a result of the 2004 Merger and
            (b) securities delivered pursuant to the CSA will be delivered on a
            timely basis in compliance with the requirements of Section 2.01 of
            the CSA and will be freely tradable and readily marketable
            securities comparable to the Contingent Shares. GGP further agrees
            to indemnify and hold harmless the Holders against losses to the
            extent arising out of any breach by GGP of the covenant in clause
            (a) or (b) of the preceding sentence.

      3.    This Agreement shall be binding upon GGP and its successors and
            assigns. This Agreement shall inure to the benefit of, and may be
            enforced by, the Representatives and/or each of the Holders and
            their respective personal or legal representatives,

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            executors, administrators, heirs, devisees legatees, successors and
            assigns to the same extent and in the same manner as a CSA may be
            enforced by them.

      4.    This Agreement and the rights and obligations of GGP hereunder shall
            be governed by and construed in accordance with the laws of the
            State of Delaware, without giving effect to the conflict of laws
            principles thereof.

      5.    This Agreement may be executed in any number of counterparts, each
            of which shall be an original, but all of which together shall
            constitute one instrument.

      6.    If the 2004 Merger Agreement is terminated prior to the Effective
            Time this Agreement shall be null and void.

      IN WITNESS WHEREOF, GGP and Rouse have executed this Agreement on the date
first above written.

                                         GENERAL GROWTH PROPERTIES, INC.

                                         By: Ronald L. Gern
                                             -----------------------------------
                                         Printed Name: Ronald L. Gern
                                         Title: Senior Vice President

                                         THE ROUSE COMPANY

                                         By: Gordon H. Glenn
                                             -----------------------------------
                                         Printed Name: Gordon H. Glenn
                                         Title: Senior Vice President