EXHIBIT 4(B)
 
                              EXTENSION AGREEMENT
 
    THIS EXTENSION AGREEMENT (this "Agreement"), is made as of the 30th day of
December, 1994 by and between MuniBond Income Fund, Inc., a Maryland corporation
and MuniAssets Fund, Inc., (collectively, the "Funds").
 
                                    RECITALS
 
    The Funds, have entered into an agreement and plan of reorganization dated
as of November 17, 1994 (the "Plan of Reorganization").
 
    In connection therewith, the Funds deem it necessary and advisable that the
Plan of Reorganization be extended beyond December 31, 1994 pursuant to this
Agreement.
 
   
    NOW, THEREFORE, the Funds hereby agree as follows:
    
 
        1. The transactions contemplated by the Plan of Reorganization have not
    been fully consummated.
 
        2. The Plan of Reorganization shall not automatically terminate,
    pursuant to its terms, on December 31, 1994.
 
        3. If the transactions contemplated by the Plan of Reorganization have
    not been fully consummated by June 30, 1995, the Plan of Reorganization
    shall automatically terminate on that date, unless a later date is mutually
    agreed to by the Boards of Directors of the respective Funds.
 
        4. The Valuation Time, as defined in Section 3(c) of the Plan of
    Reorganization, shall be 4:00 P.M., New York time, on March 10, 1995, or
    such earlier or later day and time as mutually may be agreed upon in
    writing.
 
        5. This Agreement may be signed in counterparts, which together shall
    constitute one and the same instrument.
 
        6. This Agreement shall be governed and construed in all respects in
    accordance with the laws of the State of New York.
 
    IN WITNESS WHEREOF, this Agreement has been executed as of the date and year
first above written by the undersigned for themselves and for the Funds as set
forth above.
 
                                          MUNIBOND INCOME FUND, INC.

 
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                                          MUNIASSETS FUND, INC.
 

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