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                                                                   EXHIBIT 23.5
 
                                    [LOGO]
 
                                                                  July 25, 1996
FluoroScan Imaging Systems, Inc.
650-B Anthony Trail
Northbrook, IL 60062
 
Attention: Larry Grossman
 
Gentlemen:
 
  Rodman & Renshaw, Inc. hereby consents to the inclusion of and references to
its fairness opinion dated July 18, 1996, in its entirety in the Proxy
Statement/Prospectus included in the Registration Statement on Form S-4 filed
by Hologic, Inc. and distributed to FluoroScan Imaging Systems, Inc.'s
shareholders in connection with the Agreement of Merger between FluoroScan
Imaging Systems, Inc. and Hologic, Inc.
 
                                          Very truly yours,
 
                                          Rodman & Renshaw, Inc.
 
                                                     /s/ Peter H. Blum
                                          By: _________________________________
                                                       Peter H. Blum
                                                     Managing Director
