<PAGE> PAGE 1
000 A000000 06/30/97
000 C000000 1026611
000 D000000 N
000 E000000 NF
000 F000000 Y
000 G000000 N
000 H000000 N
000 I000000 3.0.a
000 J000000 A
001 A000000 MERRIMAC FUNDS
001 B000000 811-07939
001 C000000 6173306700
002 A000000 200 CLARENDON STREET
002 B000000 BOSTON
002 C000000 MA
002 D010000 02116
003 000000 N
004 000000 N
005 000000 N
006 000000 N
007 A000000 Y
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007 C010100 1
007 C020100 MERRIMAC CASH FUND
007 C030100 N
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007 C020200 MERRIMAC TREASURY FUND
007 C030200 N
007 C010300 3
007 C010400 4
007 C010500 5
007 C010600 6
007 C010700 7
007 C010800 8
007 C010900 9
007 C011000 10
010 A00AA01 INVESTORS BANK & TRUST COMPANY
010 C01AA01 BOSTON
010 C02AA01 MA
010 C03AA01 02116
012 A00AA01 INVESTORS BANK & TRUST COMPANY
012 B00AA01 85-270
012 C01AA01 BOSTON
012 C02AA01 MA
012 C03AA01 02116
013 A00AA01 ERNST & YOUNG L.L.P.
013 B01AA01 BOSTON
013 B02AA01 MA
013 B03AA01 02116
015 A00AA01 INVESTORS BANK & TRUST COMPANY
015 B00AA01 C
<PAGE> PAGE 2
015 C01AA01 BOSTON
015 C02AA01 MA
015 C03AA01 02116
015 E01AA01 X
018 00AA00 Y
019 A00AA00 Y
019 B00AA00 4
019 C00AA00 MERRIMACIB
020 C000001 0
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022 A000001 MERRIMAC CASH PORTFOLIO
022 B000001 04-3334601
022 C000001 1148093
022 D000001 56343
022 A000002 MERRIMAC TREASURY PORTFOLIO
022 B000002 52-2021984
022 C000002 109283
022 D000002 54838
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<PAGE> PAGE 3
025 D00AA06 0
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<PAGE> PAGE 4
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066 A00AA00 N
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<PAGE> PAGE 5
070 B02AA00 N
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070 F01AA00 N
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<PAGE> PAGE 6
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<PAGE> PAGE 7
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<PAGE> PAGE 8
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<PAGE> PAGE 9
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<PAGE> PAGE 10
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SIGNATURE GEORGE M. BOYD
TITLE SECRETARY
<TABLE> <S> <C>
<ARTICLE> 6
<LEGEND>
This schedule contains summary financial information
extracted from Merrimac Cash Fund Premium Class,
form N-SAR for the period ended June 30, 1997
and is qualified in its entirety by reference to
such financial statements.
</LEGEND>
<SERIES>
<NUMBER> 1
<NAME> Merrimac Cash Fund Premium Class
<S> <C>
<PERIOD-TYPE> 6-MOS
<FISCAL-YEAR-END> DEC-31-1997
<PERIOD-END> JUN-30-1997
<INVESTMENTS-AT-COST> 1,332,246,121
<INVESTMENTS-AT-VALUE> 1,332,246,121
<RECEIVABLES> 0
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<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 1,332,307,605
<PAYABLE-FOR-SECURITIES> 0
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 108,781
<TOTAL-LIABILITIES> 108,781
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 1,325,874,992
<SHARES-COMMON-STOCK> 1,187,442,607
<SHARES-COMMON-PRIOR> 0
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<OVERDISTRIBUTION-GAINS> 0
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<NET-ASSETS> 1,325,874,992
<DIVIDEND-INCOME> 0
<INTEREST-INCOME> 31,053,603
<OTHER-INCOME> 0
<EXPENSES-NET> 1,067,611
<NET-INVESTMENT-INCOME> 29,985,992
<REALIZED-GAINS-CURRENT> 0
<APPREC-INCREASE-CURRENT> 0
<NET-CHANGE-FROM-OPS> 29,985,992
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> 30,010,802
<DISTRIBUTIONS-OF-GAINS> 0
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 801,113,000
<NUMBER-OF-SHARES-REDEEMED> 489,613,000
<SHARES-REINVESTED> 6,606
<NET-CHANGE-IN-ASSETS> 311,506,606
<ACCUMULATED-NII-PRIOR> 0
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<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
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<GROSS-EXPENSE> 1,390,811
<AVERAGE-NET-ASSETS> 1,118,427,504
<PER-SHARE-NAV-BEGIN> 1.00
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<PER-SHARE-DIVIDEND> (0.027)
<PER-SHARE-DISTRIBUTIONS> 0.00
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<PER-SHARE-NAV-END> 1.00
<EXPENSE-RATIO> 0.19
<AVG-DEBT-OUTSTANDING> 0
<AVG-DEBT-PER-SHARE> 0.00
</TABLE>
<TABLE> <S> <C>
<ARTICLE> 6
<LEGEND>
This schedule contains summary financial information
extracted from Merrimac Cash Fund Institutional Class,
form N-SAR for the period ended June 30, 1997
and is qualified in its entirety by reference to
such financial statements.
</LEGEND>
<SERIES>
<NUMBER> 2
<NAME> Merrimac Cash Fund Institutional Class
<S> <C>
<PERIOD-TYPE> 6-MOS
<FISCAL-YEAR-END> DEC-31-1997
<PERIOD-END> JUN-30-1997
<INVESTMENTS-AT-COST> 1,332,246,121
<INVESTMENTS-AT-VALUE> 1,332,246,121
<RECEIVABLES> 0
<ASSETS-OTHER> 61,484
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 1,332,307,605
<PAYABLE-FOR-SECURITIES> 0
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 108,781
<TOTAL-LIABILITIES> 108,781
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 1,325,874,992
<SHARES-COMMON-STOCK> 138,432,385
<SHARES-COMMON-PRIOR> 0
<ACCUMULATED-NII-CURRENT> 0
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> 0
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> 0
<NET-ASSETS> 1,325,874,992
<DIVIDEND-INCOME> 0
<INTEREST-INCOME> 4,240,283
<OTHER-INCOME> 0
<EXPENSES-NET> 323,200
<NET-INVESTMENT-INCOME> 3,917,083
<REALIZED-GAINS-CURRENT> 0
<APPREC-INCREASE-CURRENT> 0
<NET-CHANGE-FROM-OPS> 3,917,083
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> 3,892,273
<DISTRIBUTIONS-OF-GAINS> 0
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 346,443,845
<NUMBER-OF-SHARES-REDEEMED> 335,951,048
<SHARES-REINVESTED> 529,655
<NET-CHANGE-IN-ASSETS> 11,022,452
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> 0
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<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 1,390,811
<AVERAGE-NET-ASSETS> 145,406,468
<PER-SHARE-NAV-BEGIN> 1.00
<PER-SHARE-NII> 0.026
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<PER-SHARE-DIVIDEND> (0.026)
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<PER-SHARE-NAV-END> 1.00
<EXPENSE-RATIO> 0.44
<AVG-DEBT-OUTSTANDING> 0
<AVG-DEBT-PER-SHARE> 0.00
</TABLE>
