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<PAGE> PAGE 2
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<PAGE> PAGE 3
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<PAGE> PAGE 4
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<PAGE> PAGE 6
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SIGNATURE THOMAS ROSE
TITLE TREASURER
<TABLE> <S> <C>
<ARTICLE> 6
<SERIES>
<NUMBER> 001
<NAME> SELIGMAN COMMUNICATIONS & INFORMATION FUND, INC. CLASS A
<MULTIPLIER> 1000
<S> <C>
<PERIOD-TYPE> 6-MOS
<FISCAL-YEAR-END> DEC-31-1998
<PERIOD-END> JUN-30-1998
<INVESTMENTS-AT-COST> 4823429
<INVESTMENTS-AT-VALUE> 5341695
<RECEIVABLES> 83038
<ASSETS-OTHER> 2185
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 5426918
<PAYABLE-FOR-SECURITIES> 53683
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 60528
<TOTAL-LIABILITIES> 114211
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 4598915
<SHARES-COMMON-STOCK> 133087<F1>
<SHARES-COMMON-PRIOR> 133646<F1>
<ACCUMULATED-NII-CURRENT> (33256)
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> 228782
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> 518266
<NET-ASSETS> 3422495<F1>
<DIVIDEND-INCOME> 1842<F1>
<INTEREST-INCOME> 4525<F1>
<OTHER-INCOME> 0<F1>
<EXPENSES-NET> (23919)<F1>
<NET-INVESTMENT-INCOME> (17552)<F1>
<REALIZED-GAINS-CURRENT> 219022
<APPREC-INCREASE-CURRENT> 306007
<NET-CHANGE-FROM-OPS> 491887
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> 0<F1>
<DISTRIBUTIONS-OF-GAINS> 0<F1>
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 63683<F1>
<NUMBER-OF-SHARES-REDEEMED> (64242)<F1>
<SHARES-REINVESTED> 0<F1>
<NET-CHANGE-IN-ASSETS> 754517
<ACCUMULATED-NII-PRIOR> (114)
<ACCUMULATED-GAINS-PRIOR> 9760
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 14741<F1>
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 23919<F1>
<AVERAGE-NET-ASSETS> 3382397<F1>
<PER-SHARE-NAV-BEGIN> 23.25<F1>
<PER-SHARE-NII> (0.13)<F1>
<PER-SHARE-GAIN-APPREC> 2.60<F1>
<PER-SHARE-DIVIDEND> 0<F1>
<PER-SHARE-DISTRIBUTIONS> 0<F1>
<RETURNS-OF-CAPITAL> 0<F1>
<PER-SHARE-NAV-END> 25.72<F1>
<EXPENSE-RATIO> 1.43<F1>
<AVG-DEBT-OUTSTANDING> 0
<AVG-DEBT-PER-SHARE> 0
<FN>
<F1>Class A only. All other data are fund level.
</FN>
</TABLE>
<TABLE> <S> <C>
<ARTICLE> 6
<SERIES>
<NUMBER> 002
<NAME> SELIGMAN COMMUNICATIONS & INFORMATION FUND, INC. CLASS B
<MULTIPLIER> 1000
<S> <C>
<PERIOD-TYPE> 6-MOS
<FISCAL-YEAR-END> DEC-31-1998
<PERIOD-END> JUN-30-1998
<INVESTMENTS-AT-COST> 4823429
<INVESTMENTS-AT-VALUE> 5341695
<RECEIVABLES> 83038
<ASSETS-OTHER> 2185
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 5426918
<PAYABLE-FOR-SECURITIES> 53683
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 60528
<TOTAL-LIABILITIES> 114211
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 4598915
<SHARES-COMMON-STOCK> 33042<F1>
<SHARES-COMMON-PRIOR> 23035<F1>
<ACCUMULATED-NII-CURRENT> (33256)
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> 228782
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> 518266
<NET-ASSETS> 798669<F1>
<DIVIDEND-INCOME> 372<F1>
<INTEREST-INCOME> 912<F1>
<OTHER-INCOME> 0<F1>
<EXPENSES-NET> (7377)<F1>
<NET-INVESTMENT-INCOME> (6093)<F1>
<REALIZED-GAINS-CURRENT> 219022
<APPREC-INCREASE-CURRENT> 306007
<NET-CHANGE-FROM-OPS> 491887
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> 0<F1>
<DISTRIBUTIONS-OF-GAINS> 0<F1>
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 12022<F1>
<NUMBER-OF-SHARES-REDEEMED> (2015)<F1>
<SHARES-REINVESTED> 0<F1>
<NET-CHANGE-IN-ASSETS> 754517
<ACCUMULATED-NII-PRIOR> (114)
<ACCUMULATED-GAINS-PRIOR> 9760
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 2982<F1>
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 7377<F1>
<AVERAGE-NET-ASSETS> 682469<F1>
<PER-SHARE-NAV-BEGIN> 21.94<F1>
<PER-SHARE-NII> (0.21)<F1>
<PER-SHARE-GAIN-APPREC> 2.44<F1>
<PER-SHARE-DIVIDEND> 0<F1>
<PER-SHARE-DISTRIBUTIONS> 0<F1>
<RETURNS-OF-CAPITAL> 0<F1>
<PER-SHARE-NAV-END> 24.17<F1>
<EXPENSE-RATIO> 2.18<F1>
<AVG-DEBT-OUTSTANDING> 0
<AVG-DEBT-PER-SHARE> 0
<FN>
<F1>Class B only. All other data are fund level.
</FN>
</TABLE>
<TABLE> <S> <C>
<ARTICLE> 6
<SERIES>
<NUMBER> 004
<NAME> SELIGMAN COMMUNICATIONS & INFORMATION FUND, INC. CLASS D
<MULTIPLIER> 1000
<S> <C>
<PERIOD-TYPE> 6-MOS
<FISCAL-YEAR-END> DEC-31-1998
<PERIOD-END> JUN-30-1998
<INVESTMENTS-AT-COST> 4823429
<INVESTMENTS-AT-VALUE> 5341695
<RECEIVABLES> 83038
<ASSETS-OTHER> 2185
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 5426918
<PAYABLE-FOR-SECURITIES> 53683
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 60528
<TOTAL-LIABILITIES> 114211
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 4598915
<SHARES-COMMON-STOCK> 45207<F1>
<SHARES-COMMON-PRIOR> 43142<F1>
<ACCUMULATED-NII-CURRENT> (33256)
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> 228782
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> 518266
<NET-ASSETS> 1091543<F1>
<DIVIDEND-INCOME> 580<F1>
<INTEREST-INCOME> 1425<F1>
<OTHER-INCOME> 0<F1>
<EXPENSES-NET> (11502)<F1>
<NET-INVESTMENT-INCOME> (9497)<F1>
<REALIZED-GAINS-CURRENT> 219022
<APPREC-INCREASE-CURRENT> 306007
<NET-CHANGE-FROM-OPS> 491887
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> 0<F1>
<DISTRIBUTIONS-OF-GAINS> 0<F1>
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 25226<F1>
<NUMBER-OF-SHARES-REDEEMED> (23161)<F1>
<SHARES-REINVESTED> 0<F1>
<NET-CHANGE-IN-ASSETS> 754517
<ACCUMULATED-NII-PRIOR> (114)
<ACCUMULATED-GAINS-PRIOR> 9760
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 4647<F1>
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 11502<F1>
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<PER-SHARE-NAV-BEGIN> 21.91<F1>
<PER-SHARE-NII> (0.21)<F1>
<PER-SHARE-GAIN-APPREC> 2.45<F1>
<PER-SHARE-DIVIDEND> 0<F1>
<PER-SHARE-DISTRIBUTIONS> 0<F1>
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<FN>
<F1>Class D only. All other data are fund level.
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</TABLE>
