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                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549


                                  SCHEDULE 13G


                               (Amendment No. 1)


                              On Assignment, Inc.
--------------------------------------------------------------------------------
                                (Name of issuer)


                         COMMON STOCK, $0.01 Par Value 
--------------------------------------------------------------------------------
                         (Title of class of securities)


                                    682159108
--------------------------------------------------------------------------------
                                 (CUSIP number)


                               December 31, 2004
--------------------------------------------------------------------------------
             (Date of event which requires filing of this statement)


Check the appropriate box to designate the rule pursuant to which this Schedule
is filed:

          |_| Rule 13d-1(b)
          |X| Rule 13d-1(c)
          |_| Rule 13d-1(d)


                       (Continued on the following pages)


--------------------------------
     (1)The  remainder  of this cover  page shall be filled out for a  reporting
person's  initial  filing on this  form with  respect  to the  subject  class of
securities,  and for any subsequent amendment containing information which would
alter disclosures provided in a prior cover page.

     The  information  required on the remainder of this cover page shall not be
deemed to be "filed"  for the purpose of Section 18 of the  Securities  Exchange
Act of 1934 or otherwise  subject to the  liabilities of that section of the Act
but  shall be  subject  to all other  provisions  of the Act  (however,  see the
Notes).

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                    * SEE INSTRUCTIONS BEFORE FILLING OUT!

------------------------------    SCHEDULE 13G    ------------------------------
CUSIP No.  682159108                                         Page 2 of 10 Pages
------------------------------                    ------------------------------
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     1       NAME OF REPORTING PERSONS
             S.S. OR I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS

             Delta Partners LLC
--------------------------------------------------------------------------------
     2       CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*           (a) |_|
                                                                         (b) |X|
--------------------------------------------------------------------------------
     3       SEC USE ONLY


--------------------------------------------------------------------------------
     4       CITIZENSHIP OR PLACE OF ORGANIZATION

             State of Delaware
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      NUMBER OF          5    SOLE VOTING POWER
        SHARES                
     BENEFICIALLY             None
    OWNED BY EACH       --------------------------------------------------------
      REPORTING          6    SHARED VOTING POWER
        PERSON
         WITH                 1,430,232 common stock
                        --------------------------------------------------------
                         7    SOLE DISPOSITIVE POWER

                              None
                        --------------------------------------------------------
                         8    SHARED DISPOSITIVE POWER

                              1,430,232 common stock
--------------------------------------------------------------------------------
    9      AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

           1,430,232 common stock
--------------------------------------------------------------------------------
   10      CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*

                                                                             |_|
--------------------------------------------------------------------------------
   11      PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9

           5.7% common stock
--------------------------------------------------------------------------------
   12      TYPE OF REPORTING PERSON *

           CO, IA
================================================================================


                    * SEE INSTRUCTIONS BEFORE FILLING OUT!

------------------------------    SCHEDULE 13G    ------------------------------
CUSIP No.  682159108                                          Page 3 of 10 Pages
------------------------------                    ------------------------------
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     1       NAME OF REPORTING PERSONS
             S.S. OR I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS

             Charles Jobson
--------------------------------------------------------------------------------
     2       CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*           (a) |_|
                                                                         (b) |X|
--------------------------------------------------------------------------------
     3       SEC USE ONLY


--------------------------------------------------------------------------------
     4       CITIZENSHIP OR PLACE OF ORGANIZATION

             Massachusetts
--------------------------------------------------------------------------------
      NUMBER OF          5    SOLE VOTING POWER
        SHARES                
     BENEFICIALLY             None
    OWNED BY EACH       --------------------------------------------------------
      REPORTING          6    SHARED VOTING POWER
        PERSON
         WITH                 1,430,232 common stock
                        --------------------------------------------------------
                         7    SOLE DISPOSITIVE POWER

                              None
                        --------------------------------------------------------
                         8    SHARED DISPOSITIVE POWER

                              1,430,232 common stock
--------------------------------------------------------------------------------
    9      AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

           1,430,232 common stock
--------------------------------------------------------------------------------
   10      CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*

                                                                             |_|
--------------------------------------------------------------------------------
   11      PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9

           5.7% common stock
--------------------------------------------------------------------------------
   12      TYPE OF REPORTING PERSON *

           IN
================================================================================

                    * SEE INSTRUCTIONS BEFORE FILLING OUT!

------------------------------    SCHEDULE 13G    ------------------------------
CUSIP No.  682159108                                          Page 4 of 10 Pages
------------------------------                    ------------------------------
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     1       NAME OF REPORTING PERSONS
             S.S. OR I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS

             Christopher Argyrople
--------------------------------------------------------------------------------
     2       CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*           (a) |_|
                                                                         (b) |X|
--------------------------------------------------------------------------------
     3       SEC USE ONLY


--------------------------------------------------------------------------------
     4       CITIZENSHIP OR PLACE OF ORGANIZATION

             Massachusetts
--------------------------------------------------------------------------------
      NUMBER OF          5    SOLE VOTING POWER
        SHARES                
     BENEFICIALLY             None
    OWNED BY EACH       --------------------------------------------------------
      REPORTING          6    SHARED VOTING POWER
        PERSON
         WITH                 1,430,232 common stock
                        --------------------------------------------------------
                         7    SOLE DISPOSITIVE POWER

                              None
                        --------------------------------------------------------
                         8    SHARED DISPOSITIVE POWER

                              1,430,232 common stock
--------------------------------------------------------------------------------
    9      AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

           1,430,232 common stock
--------------------------------------------------------------------------------
   10      CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*

                                                                             |_|
--------------------------------------------------------------------------------
   11      PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9

           5.7% common stock
--------------------------------------------------------------------------------
   12      TYPE OF REPORTING PERSON *

           IN
================================================================================

                    * SEE INSTRUCTIONS BEFORE FILLING OUT!



                            STATEMENT ON SCHEDULE 13G

	
ITEM 1(a).  NAME OF ISSUER:

            On Assignment, Inc.

ITEM 1(b).  ADDRESS OF ISSUER'S PRINCIPAL EXECUTIVE OFFICES:

	    26651 West Agoura Road
	    Calabasas, CA  91302

ITEM 2(a).  NAMES OF PERSON FILING:

            
            Delta Partners LLC, a Delaware Limited Liability Company
            Charles Jobson, United States Citizen
            Christopher Argyrople, United States Citizen


ITEM 2(b).  BUSINESS MAILING ADDRESS FOR EACH PERSON FILING:

            Each of the reporting persons & entities has a business address of:

            One International Place, Suite 2401
            Boston, MA 02110


ITEM 2(c).  CITIZENSHIP:

            Shown in item 2(a) above


ITEM 2(d).  TITLE OF CLASS OF SECURITIES:

            Common Stock, $0.01 Par Value

ITEM 2(E).  CUSIP NUMBER:

                                   682159108

ITEM3. IF THIS STATEMENT IS FILED PURSUANT TO RULES 13D-1(B), OR 13D-2(B), CHECK
       WHETHER THE PERSON FILING IS A:

                                 Not Applicable

If this statement is filed pursuant to Rule 240,13d-1(c), check this box [x].


                                  Page 5 of 10


ITEM 4.  OWNERSHIP:

      DELTA PARTNERS LLC *
      (a) Amount Beneficially Owned:   1,430,232 common stock
                                     -------------------------------------------
      (b) Percent of Class:     5.7% common stock
                            ----------------------------------------------------
      (c) Number of shares as to which such person has:

          (i)  sole power to vote or to direct the vote:   None
                                                         -----------------------
          (ii) shared power to vote or to direct the vote:1,430,232 common stock
                                                           ---------------------
          (iii)sole power to dispose or to direct the disposition of: None
                                                                    ------------
          (iv)shared power to dispose or to direct the disposition of: 1,430,232
                                                                    common stock
                                                                       ---------

                                  Page 6 of 10


      

      CHARLES JOBSON *
      (a) Amount Beneficially Owned:   1,430,232 common stock
                                     -------------------------------------------
      (b) Percent of Class:    5.7% common stock
                            ----------------------------------------------------
      (c) Number of shares as to which such person has:

          (i)  sole power to vote or to direct the vote:  None
                                                         -----------------------
          (ii) shared power to vote or to direct the vote:1,430,232 common stock
                                                           ---------------------
          (iii)sole power to dispose or to direct the disposition of: None
								   
                                                                    ------------
          (iv)shared power to dispose or to direct the disposition of: 1,430,232
                                                                    common stock
                                                                       ---------



      CHRISTOPHER ARGYROPLE *
      (a) Amount Beneficially Owned:   1,430,232 common stock
                                     -------------------------------------------
      (b) Percent of Class:     5.7% common stock
                            ----------------------------------------------------
      (c) Number of shares as to which such person has:

          (i)  sole power to vote or to direct the vote:  None
                                                         -----------------------
          (ii) shared power to vote or to direct the vote:1,430,232 common stock
                                                           ---------------------
          (iii)sole power to dispose or to direct the disposition of: None
                                                                    ------------
          (iv)shared power to dispose or to direct the disposition of: 1,430,232
                                                                    common stock
                                                                       ---------


*  Shares reported  for Delta Partners, LLC,  Charles  Jobson, and Christopher  
Argyrople  include  shares  beneficially  owned by  Prism Partners L.P., Prism 
Offshore Fund Limited, and Prism Partners QP, LP. 
  


Item 5.  Ownership of Five Percent or Less of a Class:

       				 Not Applicable
                                



                                  Page 7 of 10


ITEM 6.  OWNERSHIP OF MORE THAN FIVE PERCENT ON BEHALF OF ANOTHER PERSON:

                                 Not Applicable


ITEM 7.  IDENTIFICATION  AND CLASSIFICATION OF THE SUBSIDIARY WHICH ACQUIRED THE
         SECURITY BEING REPORTED ON BY THE PARENT HOLDING COMPANY:

                                 Not Applicable


ITEM 8.  IDENTIFICATION AND CLASSIFICATION OF MEMBERS OF THE GROUP:

                                 Not Applicable


ITEM 9.  NOTICE OF DISSOLUTION OF GROUP:

                                 Not Applicable


				  Page 8 of 10



ITEM 10. CERTIFICATION:

         By  signing  below I  certify  that,  to the best of my  knowledge  and
belief, the securities  referred to above were not acquired and are not held for
the purpose of or with the effect of changing or influencing  the control of the
issuer of the  securities  and were not acquired and are not held in  connection
with or as a participant in any transaction having that purpose or effect.



                                    SIGNATURE

         After reasonable inquiry and to the best of my knowledge and belief, I
certify that the information set forth in this statement is true, complete and
correct.


Dated: February 10, 2005

                                          

                                          DELTA PARTNERS LLC
                                          By:  /s/ Chris Argyrople
                                               ---------------------------------
                                               Chris Argyrople, Managing Member


                                          CHARLES JOBSON
                                          By:  Charles Jobson
                                               ---------------------------------

                                          CHRISTOPHER ARGYROPLE
                                          By:  Christopher Argyrople
                                               ---------------------------------


                                  Page 9 of 10


                             JOINT FILING AGREEMENT


         In accordance  with Rule 13d-1(k) under the Securities  Exchange Act of
1934, as amended, the undersigned agree to the joint filing on behalf of each of
them of a statement on Schedule 13G (including  amendments thereto) with respect
to the Common Stock of On Assignment, Inc. and further agree that this agreement
be included as an  exhibit to such filing. Each party to the agreement expressly
authorizes each other party to file on its behalf any and all amendments to such
statement.  Each party to this agreement agrees that this joint filing agreement
may be signed in counterparts.

         In evidence  whereof,  the undersigned have caused this Agreement to be
executed on their behalf this 10th day of February 2005.

                                          

                                          DELTA PARTNERS LLC
                                          By:  /s/ Chris Argyrople
                                               ---------------------------------
                                               Chris Argyrople, Managing Member


                                          CHARLES JOBSON
                                          By:  Charles Jobson                   
                                               ---------------------------------

                                          CHRISTOPHER ARGYROPLE
                                          By:  Christopher Argyrople
                                               ---------------------------------



                                  Page 10 of 10