EXHIBIT 4.2



                      PPLUS TRUST CERTIFICATES SERIES SPR-1



                         AMENDMENT TO SERIES SUPPLEMENT


                                     between

                         MERRILL LYNCH DEPOSITOR, INC.,

                                  as Depositor,

                                       and

                              THE BANK OF NEW YORK,

                     as Trustee and Securities Intermediary


                          Dated as of December 12, 2003



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               AMENDMENT TO SERIES SUPPLEMENT, dated as of December 12, 2003
(the "Amendment"), by and between MERRILL LYNCH DEPOSITOR INC., a Delaware
corporation, as Depositor, THE BANK OF NEW YORK, a New York corporation, as
Trustee and Securities Intermediary.

                                   WITNESSETH:

               REFERENCE is made to the PPLUS Trust Series SPR-1 (the "Trust")
created by the Depositor by executing and delivering the Series Supplement dated
as of November 28, 2003 (the "Series Supplement"), which incorporates the terms
of the Standard Terms for Trust Agreements, dated as of February 20, 1998 (the
"Standard Terms" and, together with such Series Supplement, the "Trust
Agreement"), by and between the Depositor and the Trustee and Securities
Intermediary, as modified by such Series Supplement;

               WHEREAS, Section 3(b) of the Series Supplement permits the
Depositor to increase the amount of the Underlying Securities in the Trust and
the Trust to issue a corresponding number of additional Warrants subject to the
terms and conditions set forth in Section 3(b); and

               WHEREAS, the Depositor, on November 28, 2003, deposited
$25,475,000 Underlying Securities into the Trust and now desires to increase the
number of Underlying Securities in the Trust from $25,475,000 to $43,297,000
and, therefore, increase the number of Trust Certificates issued by the Trust
and the corresponding number of Warrants from 1,000,600 to 1,700,600;

               NOW, THEREFORE, in consideration of the foregoing premises, it is
hereby agreed by and between the Depositor and the Trustee and Securities
Intermediary as follows:

Section 1.     Amendment of Series Supplement.

               The Series Supplement is hereby amended as follows:

               (a)  All references to "1,000,600" shall be replaced with
                    "1,700,600"; and

               (b)  All references to "$25,475,000" shall be replaced with
                    "$43,297,000".

               (c)  The following definition shall be added to Section 2 of the
                    Series Supplement:

                    "Warrant" shall mean a Warrant Certificate as such term is
                    defined in the Warrant Agreement.

               (d)  The introductory clause of Section 4 of the Series
                    Supplement shall be amended to read:

                    "The Trustee hereby acknowledges receipt, with respect to
                    $25,475,000 of Underlying Securities, on or prior to the
                    Closing Date, and with respect to $17,822,000 of Underlying
                    Securities, on or prior to December 12, 2003, of:"


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Section 2.     Additional Warrant Certificates. Simultaneously with the
execution hereof, the Depositor directs the Trustee, in the name and on behalf
of the Trust, to enter into additional Warrant Certificates (as defined in the
Warrant Agreement) evidencing the additional Call Rights related to the increase
in the amount of Underlying Securities.

Section 3.     References. All references to the Series Supplement or the Trust
Agreement, in any document executed in connection with the Series Supplement,
shall be deemed to refer to the Series Supplement or the Trust Agreement, as
applicable, as amended by this Amendment.

Section 4.     Miscellaneous.

               (a) Counterparts. This Amendment may be executed by the parties
hereto in separate counterparts, each of which when so executed and delivered
shall be an original, but all such counterparts shall together constitute but
one and the same instrument.

               (b) Amendments. Neither this Amendment nor any of the terms
hereof may be terminated, amended, supplemented, waived or modified orally, but
only by an instrument in writing signed by the party against which the
enforcement of such termination, amendment, supplement, waiver or modification
is sought.

               (c) Governing Law. This Amendment shall in all respects be
construed in accordance with and governed by the laws of the State of New York,

               (d) Benefit and Binding Effect. The terms of this Amendment shall
be binding upon, and shall inure to the benefit of, the parties hereto and their
successors and permitted assigns.

               Except as amended by this Amendment, the Series Supplement
remains in full force and effect.


                                       2
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               IN WITNESS WHEREOF, the parties hereto have caused this Amendment
to be duly executed by their respective authorized officers as of the date first
written above.

                                          Merrill Lynch Depositor, Inc.,
                                          as Depositor


                                          By:  /s/ Barry N. Finkelstein
                                               -------------------------
                                          Name:    Barry N.  Finkelstein
                                          Title:   President


                                          The Bank of New York,
                                          not in its individual capacity
                                          but as Trustee


                                          By:  /s/ Ferdinand Acebedo
                                               -------------------------
                                          Name:    Ferdinand Acebedo
                                          Title:   Authorized Signatory


                                          The Bank of New York,
                                          as Securities Intermediary


                                          By:  /s/ Ferdinand Acebedo
                                               ------------------------
                                          Name:    Ferdinand Acebedo
                                          Title:   Authorized Signatory