PAGE  1
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      PAGE  2
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      PAGE  3
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      PAGE  4
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      PAGE  5
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      PAGE  6
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      PAGE  7
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      PAGE  8
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      PAGE  9
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SIGNATURE   CHARLES C. MCCOBB, JR.                       
TITLE       V.P. AND C.F.O.     

                           EXHIBIT INDEX TO FORM N-SAR
                      OF MASSMUTUAL PARTICIPATION INVESTORS
                 FOR SEMI-ANNUAL PERIOD ENDED DECEMBER 31, 2004


EXHIBIT NO.                   DESCRIPTION

77B               Accountant's Report on Internal Control

77E               Legal Proceedings

77O               Transactions Effected Pursuant to Rule 10f-3