WARNING: THE EDGAR SYSTEM ENCOUNTERED ERROR(S) WHILE PROCESSING THIS SCHEDULE.

<TABLE> <S> <C>

<ARTICLE> 6
<CIK> 0000880583
<NAME> MFS Mid Cap Growth Portfolio
<SERIES>
   <NUMBER>019
   <NAME>The Travelers Series Trust

<S>                             <C>
<PERIOD-TYPE>                  6-MOS
<FISCAL-YEAR-END>                               Dec-31-2000
<PERIOD-END>                                    Jun-30-2000
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<SHARES-COMMON-STOCK>                            12,277,878
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<EQUALIZATION>                                            0
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<EXPENSE-RATIO>                                        0.92



</TABLE>