PAGE  1
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      PAGE  2
014 A000001 BABSON CAPITAL SECURITIES INC
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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   JAMES M. ROY
TITLE       V.P. AND C.F.O.


                           EXHIBIT INDEX TO FORM N-SAR
                      OF MASSMUTUAL PARTICIPATION INVESTORS
                 FOR SEMI-ANNUAL PERIOD ENDED DECEMBER 31, 2006


EXHIBIT NO.                   DESCRIPTION

77B               Accountant's Report on Internal Controls

77O               Transactions Effected Pursuant to Rule 10f-3