FORM 3                UNITED STATES SECURITIES           OMB APPROVAL
                       AND EXCHANGE COMMISSION     OMB Number:       3235-0104
                        Washington, D.C. 20549     Expires: September 30, 1998
                                                   Estimated average burden
                                                   hours per response .... 0.5

        INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES

  Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934,
      Section 17(a) of the Public Utility Holding Company Act of 1935
                          or Section 30(f) of the
                      Investment Company Act of 1940

(Print or Type Responses)

1. Name and Address of Reporting Person*


   Morgan Stanley, Dean Witter, Discover Co.
- ----------------------------------------------
     (Last)      (First)     (Middle)



   1585 Broadway
- ------------------------------------------
                 (Street)


    New York       NY           10036
- ------------------------------------------
     (City)      (State)        (Zip)



2.   Date of Event Re-
     quiring Statement
     (Month/Day/Year)

          7/8/97


3.   IRS or Social Se-
     curity Number of
     Reporting Person
     (Voluntary)




4.   Issuer Name and Ticker or Trading Symbol

     American Industrial Properties REIT (NYSE Ticker Symbol: IND)


5.   Relationship of Reporting Person(s) to Issuer
             (Check all applicable)

     Director                   X   10% Owner
- ----                           ----

     Officer (give                  Other (specify
- ---- title below)              ----       below)



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




6.   If Amendment, Date of
     Original (Month/Day/Year)



7.   Individual or Joint/Group
     Filing (Check Applicable Line)

 X    Form filed One Reporting Person
- ----

      Form filed by More than One Reporting Person
- ----


                          Table I -- Non-Derivative Securities Beneficially Owned



1. Title of Security                 2. Amount of Securities    3. Ownership         4. Nature of Indirect Beneficial
   (Instr. 4)                           Beneficially Owned         Form: Direct         Ownership (Instr. 5)
                                        (Instr. 4)                 (D) or Indirect
                                                                   (I) (Instr. 5)
- -------------------------------------------------------------------------------------------------------------------------------
                                                                               
Common Shares of Beneficial                                         (I)   627,943       Throgh Corporation
  Interest                                658,269                   (I)    30,326       Through Partnership
















Reminder: Report on a separate line for each class of securities
beneficially owned directly or indirectly.

* If the form is filed by more than one reporting person,               (Over)
see Instruction 5(b)(v).                                       SEC 1473 (7-96)





FORM 3 (continued)     Table II  Derivative Securities Beneficially Owned
                       (e.g., puts, calls, warrants, options, convertible securities)


                                                                                             

















Explanation of Responses:



**Intentional misstatements or omissions of facts constitute Federal
  Criminal Violations.
  See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).

Note: File three copies of this Form, one of which must be manually signed.
      If space is insufficient, See Instruction 6 for procedure.

Potential persons who are to respond to the collection of information
contained in this form are not required to respond unless the form
displays a currently valid OMB Number.



Morgan Stanley, Dean Witter, Discover & Co.

By:   /s/ Stewart J. M. Breslow                            July 18, 1997
   ---------------------------------                   -----------------------
   **Signature of Reporting Person                               Date

Name:  Stewart J. M. Breslow
Title: Authorized Signer


                                                                        Page 2
                                                               SEC 1473 (7-96)