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                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549
                            ------------------------
 
                                  FORM 10-K/A
 
[X]  ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE
     SECURITIES EXCHANGE ACT OF 1934.
 
                  FOR THE FISCAL YEAR ENDED DECEMBER 31, 1998
 
                                       OR
 
[ ]  TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE
     SECURITIES EXCHANGE ACT OF 1934.
 
          FOR THE TRANSITION PERIOD FROM ____________ TO ____________
 
                        COMMISSION FILE NUMBER: 1-11665
 
                             JEFFERIES GROUP, INC.
             (EXACT NAME OF REGISTRANT AS SPECIFIED IN ITS CHARTER)
 
<TABLE>
<S>                                            <C>
                   DELAWARE                                      95-2848406
       (STATE OR OTHER JURISDICTION OF                        (I.R.S. EMPLOYER
        INCORPORATION OR ORGANIZATION)                      IDENTIFICATION NO.)
 
   11100 SANTA MONICA BOULEVARD, 11TH FLOOR                        90025
           LOS ANGELES, CALIFORNIA                               (ZIP CODE)
   (ADDRESS OF PRINCIPAL EXECUTIVE OFFICES)
</TABLE>
 
              REGISTRANT'S TELEPHONE NUMBER, INCLUDING AREA CODE:
                                 (310) 445-1199
 
          SECURITIES REGISTERED PURSUANT TO SECTION 12(b) OF THE ACT:
                 COMMON STOCK, $.01 PAR VALUE (TITLE OF CLASS)
 
          SECURITIES REGISTERED PURSUANT TO SECTION 12(g) OF THE ACT:
 
     Indicate by check mark whether the registrant (1) has filed all reports
required to be filed by Section 13 or 15(d) of the Securities Exchange Act of
1934 during the preceding 12 months (or for such shorter period that the
registrant was required to file such reports), and (2) has been subject to such
filing requirements for the past 90 days. Yes  [X]   No  [ ]
 
     Indicate by check mark if disclosure of delinquent filers pursuant to Item
405 of Regulation S-K is not contained herein, and will not be contained, to the
best of registrant's knowledge in definitive proxy or information statements
incorporated by reference in Part III of this Form 10-K, or any amendment to
this Form 10-K. [ ]
 
     State the aggregate market value of the common stock held by nonaffiliates
of the registrant. $809,846,676 as of March 8, 1999.
 
     Indicate the number of shares outstanding of the registrant's class of
common stock, as of the latest practical date. 23,961,913 shares as of the close
of business March 8, 1999.
 
                      DOCUMENTS INCORPORATED BY REFERENCE
                          See list on following page.
 
                           LOCATION OF EXHIBIT INDEX
        The index of exhibits is contained in Part IV herein on page 54.
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          Jefferies Group, Inc. hereby amends Item 14(a)3 of its annual report 
on Form 10-K for 1998 by deleting current Exhibit 3.1 in its entirety and 
substituting new Exhibit 3.1 as follows:

          (3.1)     Amended and Restated Certificate of Incorporation
                    of Jefferies Group, Inc.




                                   SIGNATURES

          Pursuant to the requirements of the Securities Exchange Act of 1934, 
the Registrant has duly caused this report to be signed on its behalf by the 
undersigned, thereunto duly authorized.


                                          JEFFERIES GROUP, INC.


                                          By:   /s/ JERRY M. GLUCK
                                             ---------------------------------
                                                    Jerry M. Gluck
                                                    Secretary


Dated:  March 26, 1999