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<PAGE> PAGE 2
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018 00AA00 Y
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<PAGE> PAGE 3
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<PAGE> PAGE 4
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<PAGE> PAGE 5
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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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<PAGE> PAGE 11
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<PAGE> PAGE 12
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SIGNATURE PAUL JASINSKI
TITLE TREASURER
<TABLE> <S> <C>
<ARTICLE> 6
<LEGEND>
This schedule contains summary financial information
extracted from The Merrimac Cash Portfolio
form N-SAR for the period ended December 31, 1998
and is qualified in its entirety by reference to
such financial statements.
</LEGEND>
<SERIES>
<NUMBER> 1
<NAME> Merrimac Cash Portfolio
<S> <C>
<PERIOD-TYPE> 12-MOS
<FISCAL-YEAR-END> DEC-31-1998
<PERIOD-END> DEC-31-1998
<INVESTMENTS-AT-COST> 782,556,187
<INVESTMENTS-AT-VALUE> 782,556,187
<RECEIVABLES> 10,539,721
<ASSETS-OTHER> 155,730
<OTHER-ITEMS-ASSETS> 146,268
<TOTAL-ASSETS> 793,397,906
<PAYABLE-FOR-SECURITIES> 0
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 198,059
<TOTAL-LIABILITIES> 198,059
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 793,199,847
<SHARES-COMMON-STOCK> 0
<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> 793,199,847
<DIVIDEND-INCOME> 0
<INTEREST-INCOME> 58,239,893
<OTHER-INCOME> 0
<EXPENSES-NET> 1,561,435
<NET-INVESTMENT-INCOME> 56,678,458
<REALIZED-GAINS-CURRENT> 13,660
<APPREC-INCREASE-CURRENT> 0
<NET-CHANGE-FROM-OPS> 56,692,118
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> 0
<DISTRIBUTIONS-OF-GAINS> 0
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 3,737,889,197
<NUMBER-OF-SHARES-REDEEMED> 4,386,229,061
<SHARES-REINVESTED> 0
<NET-CHANGE-IN-ASSETS> (591,647,746)
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> 0
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 1,760,305
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 1,945,648
<AVERAGE-NET-ASSETS> 1,035,618,373
<PER-SHARE-NAV-BEGIN> 0.00
<PER-SHARE-NII> 0.00
<PER-SHARE-GAIN-APPREC> 0.00
<PER-SHARE-DIVIDEND> 0.00
<PER-SHARE-DISTRIBUTIONS> 0
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 0.00
<EXPENSE-RATIO> 0.15
<AVG-DEBT-OUTSTANDING> 0
<AVG-DEBT-PER-SHARE> 0
</TABLE>
<TABLE> <S> <C>
<ARTICLE> 6
<LEGEND>
This schedule contains summary financial information
extracted from The Merrimac Treasury Portfolio
form N-SAR for the period ended December 31, 1998
and is qualified in its entirety by reference to
such financial statements.
</LEGEND>
<SERIES>
<NUMBER> 2
<NAME> Merrimac Treasury Portfolio
<S> <C>
<PERIOD-TYPE> 12-MOS
<FISCAL-YEAR-END> DEC-31-1998
<PERIOD-END> DEC-31-1998
<INVESTMENTS-AT-COST> 113,893,315
<INVESTMENTS-AT-VALUE> 113,893,315
<RECEIVABLES> 858,458
<ASSETS-OTHER> 717
<OTHER-ITEMS-ASSETS> 25,902
<TOTAL-ASSETS> 114,778,392
<PAYABLE-FOR-SECURITIES> 0
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 52,451
<TOTAL-LIABILITIES> 52,451
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 114,725,941
<SHARES-COMMON-STOCK> 0
<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> 114,725,941
<DIVIDEND-INCOME> 0
<INTEREST-INCOME> 2,884,352
<OTHER-INCOME> 0
<EXPENSES-NET> 149,802
<NET-INVESTMENT-INCOME> 2,734,550
<REALIZED-GAINS-CURRENT> 966
<APPREC-INCREASE-CURRENT> 0
<NET-CHANGE-FROM-OPS> 2,735,516
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> 0
<DISTRIBUTIONS-OF-GAINS> 0
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 360,772,130
<NUMBER-OF-SHARES-REDEEMED> 322,698,051
<SHARES-REINVESTED> 0
<NET-CHANGE-IN-ASSETS> 40,809,595
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> 0
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 98,068
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 149,802
<AVERAGE-NET-ASSETS> 57,695,312
<PER-SHARE-NAV-BEGIN> 0.00
<PER-SHARE-NII> 0.00
<PER-SHARE-GAIN-APPREC> 0.00
<PER-SHARE-DIVIDEND> 0.00
<PER-SHARE-DISTRIBUTIONS> 0
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 0.00
<EXPENSE-RATIO> 0.26
<AVG-DEBT-OUTSTANDING> 0
<AVG-DEBT-PER-SHARE> 0
</TABLE>
Report of Ernst & Young LLP, Independent Auditors
To the Board of Trustees and
Owners of Beneficial Interest of
Merrimac Master Portfolio
In planning and performing our audit of the financial statements of the Merrimac
Cash Portfolio and the Merrimac Treasury Portfolio, the two series comprising
the Merrimac Master Portfolio (collectively, the "Portfolio Trust") for the year
ended December 31, 1998, we considered its internal control, including control
activities for safeguarding securities, in order to determine our auditing
procedures for the purpose of expressing our opinion on the financial statements
and to comply with the requirements of Form N-SAR, and not to provide assurance
on the internal control.
The management of the Portfolio Trust is responsible for establishing and
maintaining internal control. In fulfilling this responsibility, estimates and
judgments by management are required to assess the expected benefits and related
costs of controls. Generally, controls that are relevant to an audit pertain to
the entity's objective of preparing financial statements for external purposes
that are fairly presented in conformity with generally accepted accounting
principles. Those controls include the safeguarding of assets against
unauthorized acquisition, use or disposition.
Because of inherent limitations in internal control, errors or fraud may occur
and not be detected. Also, projection of any evaluation of internal control to
future periods is subject to the risk that it may become inadequate because of
changes in conditions or that the effectiveness of the design and operation may
deteriorate.
Our consideration of internal control would not necessarily disclose all matters
in internal control that might be material weaknesses under standards
established by the American Institute of Certified Public Accountants. A
material weakness is a condition in which the design or operation of one or more
of specific internal control components does not reduce to a relatively low
level the risk that errors or fraud in amounts that would be material in
relation to the financial statements being audited may occur and not be detected
within a timely period by employees in the normal course of performing their
assigned functions. However, we noted no matters involving internal control and
its operation, including controls for safeguarding securities, that we consider
to be material weaknesses as defined above at December 31, 1998.
This report is intended solely for the information and use of the board of
trustees and management of the Portfolio Trust and the Securities and Exchange
Commission and is not intended to be and should not be used by anyone other than
these specified parties.
Boston, Massachusetts
February 12, 1999
14
L:\MFADMIN\MERRIMAC\BOARD\981026\INVEST.DOC
Merrimac Master Portfolio
("Master Trust")
Merrimac Funds
("Feeder Trust 1")
Merrimac Series
("Feeder Trust 2")
Combined Board of Trustees
Meeting
October 26, 1998
APPROVAL OF CHANGE TO INVESTMENT POLICIES
Master/Feeder Trust 1 & 2
WHEREAS, the non-fundamental investment policies of the Merrimac
Treasury Portfolio, (the "Portfolio"), a series of the Merrimac Master
Portfolio, the Merrimac Treasury Fund (the "Fund"), a series of
Merrimac Funds, and the Merrimac Treasury Series (the "Series"), a
series of Merrimac Series, represent the current intentions of the
Board of Trustees and of the Portfolio, the Fund and the Series; and
WHEREAS, non-fundamental investment policies may be changed or amended
by the Board of Trustees of the Merrimac Master Portfolio, Merrimac
Funds and Merrimac Series without prior notice to or approval by
shareholders; it is hereby
RESOLVED, that the changes to the investment policies of the Portfolio,
the Fund and the Series, as reflected in the Prospectus and Statement
of Additional Information for the Series presented to the Trustees at
the Meeting be, and they hereby are, approved.
