<ARTICLE> 5
<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM THE
CONSOLIDATED BALANCE SHEETS, STATEMENTS OF OPERATIONS AND STATEMENTS OF CASH
FLOWS INCLUDED IN THE COMPANY'S FORM 10-Q FOR THE PERIOD ENDED JUNE 30, 1997,
AND IS QUALIFIED IN ITS ENTIRETY BY REFERENCE TO SUCH FINANCIAL STATEMENTS AND
NOTES THERETO.
</LEGEND>
<MULTIPLIER> 1,000
       
                             
<PERIOD-TYPE>                   6-MOS
<FISCAL-YEAR-END>                          DEC-31-1997
<PERIOD-START>                             JAN-01-1997
<PERIOD-END>                               JUN-30-1997
<CASH>                                          19,451
<SECURITIES>                                    28,222
<RECEIVABLES>                                        0
<ALLOWANCES>                                         0
<INVENTORY>                                          0
<CURRENT-ASSETS>                                50,504
<PP&E>                                          24,070
<DEPRECIATION>                                (11,352)
<TOTAL-ASSETS>                                  76,862
<CURRENT-LIABILITIES>                           14,537
<BONDS>                                              0
<PREFERRED-MANDATORY>                                0
<PREFERRED>                                          0
<COMMON>                                        14,981
<OTHER-SE>                                      49,163
<TOTAL-LIABILITY-AND-EQUITY>                    76,862
<SALES>                                              0
<TOTAL-REVENUES>                                12,865
<CGS>                                                0
<TOTAL-COSTS>                                        0
<OTHER-EXPENSES>                                18,517
<LOSS-PROVISION>                                     0
<INTEREST-EXPENSE>                                 382
<INCOME-PRETAX>                                (4,265)
<INCOME-TAX>                                         0
<INCOME-CONTINUING>                            (4,265)
<DISCONTINUED>                                       0
<EXTRAORDINARY>                                      0
<CHANGES>                                            0
<NET-INCOME>                                   (4,265)
<EPS-PRIMARY>                                    (.29)
<EPS-DILUTED>                                    (.29)