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<PAGE> PAGE 2
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013 A00AA01 ERNST & YOUNG
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<PAGE> PAGE 3
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<PAGE> PAGE 9
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SIGNATURE GEORGE M.BOYD
TITLE SECRETARY
<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, 1996
and is qualified in its entirety by reference to
such financial statements.
</LEGEND>
<S> <C>
<PERIOD-TYPE> 12-MOS
<FISCAL-YEAR-END> DEC-31-1996
<PERIOD-END> DEC-31-1996
<INVESTMENTS-AT-COST> 1,005,827,311
<INVESTMENTS-AT-VALUE> 1,005,827,311
<RECEIVABLES> 487,659
<ASSETS-OTHER> 58,652
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 1,006,373,622
<PAYABLE-FOR-SECURITIES> 0
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 63,477
<TOTAL-LIABILITIES> 63,477
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 1,006,310,145
<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> 1,006,310,145
<DIVIDEND-INCOME> 0
<INTEREST-INCOME> 3,572,665
<OTHER-INCOME> 0
<EXPENSES-NET> 78,760
<NET-INVESTMENT-INCOME> 3,493,905
<REALIZED-GAINS-CURRENT> 0
<APPREC-INCREASE-CURRENT> 0
<NET-CHANGE-FROM-OPS> 3,493,905
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> 0
<DISTRIBUTIONS-OF-GAINS> 0
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 0
<NUMBER-OF-SHARES-REDEEMED> 0
<SHARES-REINVESTED> 0
<NET-CHANGE-IN-ASSETS> 1,006,310,145
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> 0
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 108,913
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 136,420
<AVERAGE-NET-ASSETS> 571,907,587
<PER-SHARE-NAV-BEGIN> 0.00
<PER-SHARE-NII> 0.00
<PER-SHARE-GAIN-APPREC> 0.00
<PER-SHARE-DIVIDEND> 0.00
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</TABLE>
Board of Trustees
Merrimac Master Portfolio
In planning and performing our audits of the financial statements of the
Merrimac Cash Portfolio (one of the series of the Merrimac Master Portfolio) for
the period ended December 31, 1996, we considered its internal control
structure, including procedures 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, not
to provide assurance on the internal control structure.
The management of the Merrimac Cash Portfolio is responsible for establishing
and maintaining an internal control structure. In fulfilling this
responsibility, estimates and judgments by management are required to assess the
expected benefits and related costs of internal control structure policies and
procedures. Two of the objectives of an internal control structure are to
provide management with reasonable, but not absolute, assurance that assets are
safeguarded against loss from unauthorized use or disposition and that
transactions are executed in accordance with management's authorization and
recorded properly to permit preparation of financial statements in conformity
with generally accepted accounting principles.
Because of inherent limitations in any internal control structure, errors or
irregularities may occur and not be detected. Also, projection of any evaluation
of the structure 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 the internal control structure would not necessarily
disclose all matters in the internal control structure 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 the specific internal control structure elements does not reduce to
a relatively low level the risk that errors or irregularities 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 the internal control structure, including procedures for safeguarding
securities, that we consider to be material weaknesses as defined above at
December 31, 1996.
This report is intended solely for the information and use of management and the
Securities and Exchange Commission.
/S/ ERNST & YOUNG LLP
February 21, 1997
Merrimac Master Portfolio
Special Meeting of Holder in Interest
October 30, 1996
A meeting of the Holder in Interest of the Merrimac Master
Portfolio (the "Trust") was held at 4:00 p.m. on October 30,
1996 at 89 South Street, Boston, Massachusetts to consider the
election of the Trustees of the Trust, approval of the
Investment Adviser Agreement and the Investment Sub-Adviser
Agreement, and the selection of independent auditors for the
Trust.
After the meeting was called to order, Francis J. Gaul, Jr., the
only Holder in Interest of the Trust, took the following
actions, upon motion duly made and seconded:
RESOLVED, That the following persons be, and hereby are,
elected to serve as Trustees of the Trust to serve until
the next meeting of Holders of Interest called for the
purpose of electing Trustees or until he sooner dies,
resigns or is removed from office: Edward F. Hines, Jr.,
Francis J. Gaul, Jr., Kevin J. Sheehan and Thomas E. Sinton;
RESOLVED FURTHER, That the Investment Adviser Agreement
between the Trust and Investors Bank & Trust Company dated
October 30, 1996, including the fee schedule set forth
therein, be, and hereby is approved;
RESOLVED FURTHER, That the Investment Sub-Adviser Agreement
between Investors Bank & Trust Company and The Bank of New
York dated October 30, 1996, including the fee schedule set
forth therein, be, and hereby is approved; and
RESOLVED, FURTHER, That the firm of Ernst & Young LLP be,
and hereby is, appointed as the independent auditor for the
Trust for the fiscal year ended December 31, 1996.
There being no further business to come before the meeting, the
meeting was adjourned.
/s/ George M. Boyd
------------------
George M. Boyd
Secretary
The undersigned, being the only Holder in Interest of the Trust,
hereby waives notice of the foregoing meeting, approves the
minutes thereof and ratifies and confirms all actions taken at
such meeting.
/s/ Francis J. Gaul, Jr.
- ------------------------
Francis J. Gaul, Jr.
Holder in Interest
