<PAGE> PAGE 1
000 B000000 09/30/99
000 C000000 750756
000 D000000 N
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000 H000000 N
000 I000000 3.0.a
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007 C020200 CALIFORNIA HIGH-YIELD SERIES
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007 C010300 3
007 C010400 4
007 C020400 NORTH CAROLINA SERIES
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007 C010500 5
007 C020500 FLORIDA SERIES
007 C030500 N
007 C010600 6
007 C010700 7
007 C010800 8
007 C010900 9
007 C011000 10
008 A00AA01 J. & W. SELIGMAN & CO., INCORPORATED
008 B00AA01 A
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018 00AA00 Y
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<PAGE> PAGE 2
020 C000002 0
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022 B000001 13-2518466
022 C000001 41874
022 D000001 39820
022 A000002 MERRILL LYNCH, PIERCE, FENNER & SMITH INC.
022 B000002 13-5674085
022 C000002 15215
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022 A000003 BEAR STEARNS & CO., INC.
022 B000003 13-3299429
022 C000003 13247
022 D000003 6310
022 A000004 SALOMON SMITH BARNEY & CO.,INC.
022 B000004 11-2418191
022 C000004 9056
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022 A000005 PIPER JAFFRAY INC.
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022 B000006 22-2347336
022 C000006 2986
022 D000006 5007
022 A000007 GOLDMAN SACHS & CO.
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022 C000007 7500
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022 C000009 2989
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022 A000010 PRAGER, MCCARTHY & SEALY
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<PAGE> PAGE 3
023 D000000 100137
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<PAGE> PAGE 4
049 00AA00 N
050 00AA00 N
051 00AA00 N
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054 D00AA00 N
054 E00AA00 N
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<PAGE> PAGE 5
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<PAGE> PAGE 6
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<PAGE> PAGE 7
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<PAGE> PAGE 8
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<PAGE> PAGE 9
028 B030200 0
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<PAGE> PAGE 10
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<PAGE> PAGE 11
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<PAGE> PAGE 12
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<PAGE> PAGE 13
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<PAGE> PAGE 14
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<PAGE> PAGE 15
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<PAGE> PAGE 16
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<PAGE> PAGE 17
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<PAGE> PAGE 18
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<PAGE> PAGE 19
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SIGNATURE THOMAS G. ROSE
TITLE TREASURER
WARNING: THE EDGAR SYSTEM ENCOUNTERED ERROR(S) WHILE PROCESSING THIS SCHEDULE.
<TABLE> <S> <C>
<ARTICLE> 6
<SERIES>
<NUMBER>021
<NAME> SELIGMAN MUNICIPAL SERIES TRUST-CALIFORNIA HIGH-YIELD CL A
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<APPREC-INCREASE-CURRENT> (6115)
<NET-CHANGE-FROM-OPS> (2144)
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> (2826)<F1>
<DISTRIBUTIONS-OF-GAINS> (208)<F1>
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 3487<F1>
<NUMBER-OF-SHARES-REDEEMED> (3136)<F1>
<SHARES-REINVESTED> 264<F1>
<NET-CHANGE-IN-ASSETS> 1739
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> 162
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 299<F1>
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 503<F1>
<AVERAGE-NET-ASSETS> 59884<F1>
<PER-SHARE-NAV-BEGIN> 6.80<F1>
<PER-SHARE-NII> .31<F1>
<PER-SHARE-GAIN-APPREC> (.50)<F1>
<PER-SHARE-DIVIDEND> (.31)<F1>
<PER-SHARE-DISTRIBUTIONS> (.02)<F1>
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 6.28<F1>
<EXPENSE-RATIO> .84<F1>
[AVG-DEBT-OUTSTANDING] 0
[AVG-DEBT-PER-SHARE] 0
<FN>
<F1>Class A only. All other data are fund level.
</FN>
</TABLE>
WARNING: THE EDGAR SYSTEM ENCOUNTERED ERROR(S) WHILE PROCESSING THIS SCHEDULE.
<TABLE> <S> <C>
<ARTICLE> 6
<SERIES>
<NUMBER>023
<NAME> SELIGMAN MUNICIPAL SERIES TRUST-CALIFORNIA HIGH-YIELD CL C
<MULTIPLIER> 1000
<S> <C>
<PERIOD-TYPE> 12-MOS
<FISCAL-YEAR-END> SEP-30-1999
<PERIOD-END> SEP-30-1999
<INVESTMENTS-AT-COST> 66695
<INVESTMENTS-AT-VALUE> 65324
<RECEIVABLES> 1350
<ASSETS-OTHER> 72
<OTHER-ITEMS-ASSETS> 6
<TOTAL-ASSETS> 66752
<PAYABLE-FOR-SECURITIES> 0
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 246
<TOTAL-LIABILITIES> 246
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 67099
<SHARES-COMMON-STOCK> 166<F1>
<SHARES-COMMON-PRIOR> 0<F1>
<ACCUMULATED-NII-CURRENT> 0
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> 778
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> (1371)
<NET-ASSETS> 1041<F1>
<DIVIDEND-INCOME> 0
<INTEREST-INCOME> 11<F1>
<OTHER-INCOME> 0
<EXPENSES-NET> (3)<F1>
<NET-INVESTMENT-INCOME> 8<F1>
<REALIZED-GAINS-CURRENT> 848
<APPREC-INCREASE-CURRENT> (6115)
<NET-CHANGE-FROM-OPS> (2144)
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> (8)<F1>
<DISTRIBUTIONS-OF-GAINS> 0<F1>
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 166<F1>
<NUMBER-OF-SHARES-REDEEMED> 0<F1>
<SHARES-REINVESTED> 1<F1>
<NET-CHANGE-IN-ASSETS> 1739
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> 162
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 1<F1>
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 3<F1>
<AVERAGE-NET-ASSETS> 551<F1>
<PER-SHARE-NAV-BEGIN> 6.62<F1>
<PER-SHARE-NII> .09<F1>
<PER-SHARE-GAIN-APPREC> (.33)<F1>
<PER-SHARE-DIVIDEND> (.09)<F1>
<PER-SHARE-DISTRIBUTIONS> 0<F1>
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 6.29<F1>
<EXPENSE-RATIO> 1.74<F1>
[AVG-DEBT-OUTSTANDING] 0
[AVG-DEBT-PER-SHARE] 0
<FN>
<F1>Class C only. All other data are fund level.
</FN>
</TABLE>
WARNING: THE EDGAR SYSTEM ENCOUNTERED ERROR(S) WHILE PROCESSING THIS SCHEDULE.
<TABLE> <S> <C>
<ARTICLE> 6
<SERIES>
<NUMBER>024
<NAME> SELIGMAN MUNICIPAL SERIES TRUST-CALIFORNIA HIGH-YIELD CL D
<MULTIPLIER> 1000
<S> <C>
<PERIOD-TYPE> 12-MOS
<FISCAL-YEAR-END> SEP-30-1999
<PERIOD-END> SEP-30-1999
<INVESTMENTS-AT-COST> 66695
<INVESTMENTS-AT-VALUE> 65324
<RECEIVABLES> 1350
<ASSETS-OTHER> 72
<OTHER-ITEMS-ASSETS> 6
<TOTAL-ASSETS> 66752
<PAYABLE-FOR-SECURITIES> 0
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 246
<TOTAL-LIABILITIES> 246
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 67099
<SHARES-COMMON-STOCK> 1218<F1>
<SHARES-COMMON-PRIOR> 940<F1>
<ACCUMULATED-NII-CURRENT> 0
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> 778
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> (1371)
<NET-ASSETS> 7658<F1>
<DIVIDEND-INCOME> 0
<INTEREST-INCOME> 421<F1>
<OTHER-INCOME> 0
<EXPENSES-NET> (132)<F1>
<NET-INVESTMENT-INCOME> 289<F1>
<REALIZED-GAINS-CURRENT> 848
<APPREC-INCREASE-CURRENT> (6115)
<NET-CHANGE-FROM-OPS> (2144)
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> (289)<F1>
<DISTRIBUTIONS-OF-GAINS> (24)<F1>
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 505<F1>
<NUMBER-OF-SHARES-REDEEMED> (262)<F1>
<SHARES-REINVESTED> 35<F1>
<NET-CHANGE-IN-ASSETS> 1739
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> 162
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 38<F1>
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 132<F1>
<AVERAGE-NET-ASSETS> 7593<F1>
<PER-SHARE-NAV-BEGIN> 6.80<F1>
<PER-SHARE-NII> .25<F1>
<PER-SHARE-GAIN-APPREC> (.49)<F1>
<PER-SHARE-DIVIDEND> (.25)<F1>
<PER-SHARE-DISTRIBUTIONS> (.02)<F1>
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 6.29<F1>
<EXPENSE-RATIO> 1.74<F1>
[AVG-DEBT-OUTSTANDING] 0
[AVG-DEBT-PER-SHARE] 0
<FN>
<F1>Class D only. All other data are fund level.
</FN>
</TABLE>
WARNING: THE EDGAR SYSTEM ENCOUNTERED ERROR(S) WHILE PROCESSING THIS SCHEDULE.
<TABLE> <S> <C>
<ARTICLE> 6
<SERIES>
<NUMBER>011
<NAME> SELIGMAN MUNICIPAL SERIES TRUST-CALIFORNIA QUALITY CL A
<MULTIPLIER> 1000
<S> <C>
<PERIOD-TYPE> 12-MOS
<FISCAL-YEAR-END> SEP-30-1999
<PERIOD-END> SEP-30-1999
<INVESTMENTS-AT-COST> 79158
<INVESTMENTS-AT-VALUE> 77702
<RECEIVABLES> 1539
<ASSETS-OTHER> 84
<OTHER-ITEMS-ASSETS> 7
<TOTAL-ASSETS> 79332
<PAYABLE-FOR-SECURITIES> 0
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 243
<TOTAL-LIABILITIES> 243
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 79961
<SHARES-COMMON-STOCK> 11649<F1>
<SHARES-COMMON-PRIOR> 12142<F1>
<ACCUMULATED-NII-CURRENT> 0
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> 584
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> (1456)
<NET-ASSETS> 74793<F1>
<DIVIDEND-INCOME> 0
<INTEREST-INCOME> 4422<F1>
<OTHER-INCOME> 0
<EXPENSES-NET> (674)<F1>
<NET-INVESTMENT-INCOME> 3748<F1>
<REALIZED-GAINS-CURRENT> 968
<APPREC-INCREASE-CURRENT> (8038)
<NET-CHANGE-FROM-OPS> (3158)
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> (3748)<F1>
<DISTRIBUTIONS-OF-GAINS> (2763)<F1>
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 577<F1>
<NUMBER-OF-SHARES-REDEEMED> (1585)<F1>
<SHARES-REINVESTED> 515<F1>
<NET-CHANGE-IN-ASSETS> (10735)
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> 2480
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 411<F1>
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 674<F1>
<AVERAGE-NET-ASSETS> 82201<F1>
<PER-SHARE-NAV-BEGIN> 7.21<F1>
<PER-SHARE-NII> .31<F1>
<PER-SHARE-GAIN-APPREC> (.56)<F1>
<PER-SHARE-DIVIDEND> (.31)<F1>
<PER-SHARE-DISTRIBUTIONS> (.23)<F1>
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 6.42<F1>
<EXPENSE-RATIO> .82<F1>
[AVG-DEBT-OUTSTANDING] 0
[AVG-DEBT-PER-SHARE] 0
<FN>
<F1>Class A only. All other data are fund level.
</FN>
</TABLE>
WARNING: THE EDGAR SYSTEM ENCOUNTERED ERROR(S) WHILE PROCESSING THIS SCHEDULE.
<TABLE> <S> <C>
<ARTICLE> 6
<SERIES>
<NUMBER>013
<NAME> SELIGMAN MUNICIPAL SERIES TRUST-CALIFORNIA QUALITY CL C
<MULTIPLIER> 1000
<S> <C>
<PERIOD-TYPE> 12-MOS
<FISCAL-YEAR-END> SEP-30-1999
<PERIOD-END> SEP-30-1999
<INVESTMENTS-AT-COST> 79158
<INVESTMENTS-AT-VALUE> 77702
<RECEIVABLES> 1539
<ASSETS-OTHER> 84
<OTHER-ITEMS-ASSETS> 7
<TOTAL-ASSETS> 79332
<PAYABLE-FOR-SECURITIES> 0
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 243
<TOTAL-LIABILITIES> 243
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 79961
<SHARES-COMMON-STOCK> 1<F1>
<SHARES-COMMON-PRIOR> 0<F1>
<ACCUMULATED-NII-CURRENT> 0
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> 584
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> (1456)
<NET-ASSETS> 10<F1>
<DIVIDEND-INCOME> 0
<INTEREST-INCOME> 0<F1>
<OTHER-INCOME> 0
<EXPENSES-NET> 0<F1>
<NET-INVESTMENT-INCOME> 0<F1>
<REALIZED-GAINS-CURRENT> 968
<APPREC-INCREASE-CURRENT> (8038)
<NET-CHANGE-FROM-OPS> (3158)
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> 0<F1>
<DISTRIBUTIONS-OF-GAINS> 0<F1>
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 1<F1>
<NUMBER-OF-SHARES-REDEEMED> 0<F1>
<SHARES-REINVESTED> 0<F1>
<NET-CHANGE-IN-ASSETS> (10735)
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> 2480
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 0<F1>
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 3<F1>
<AVERAGE-NET-ASSETS> 9<F1>
<PER-SHARE-NAV-BEGIN> 6.75<F1>
<PER-SHARE-NII> .09<F1>
<PER-SHARE-GAIN-APPREC> (.35)<F1>
<PER-SHARE-DIVIDEND> (.09)<F1>
<PER-SHARE-DISTRIBUTIONS> 0<F1>
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 6.40<F1>
<EXPENSE-RATIO> 1.72<F1>
[AVG-DEBT-OUTSTANDING] 0
[AVG-DEBT-PER-SHARE] 0
<FN>
<F1>Class C only. All other data are fund level.
</FN>
</TABLE>
WARNING: THE EDGAR SYSTEM ENCOUNTERED ERROR(S) WHILE PROCESSING THIS SCHEDULE.
<TABLE> <S> <C>
<ARTICLE> 6
<SERIES>
<NUMBER>014
<NAME> SELIGMAN MUNICIPAL SERIES TRUST-CALIFORNIA QUALITY CL D
<MULTIPLIER> 1000
<S> <C>
<PERIOD-TYPE> 12-MOS
<FISCAL-YEAR-END> SEP-30-1999
<PERIOD-END> SEP-30-1999
<INVESTMENTS-AT-COST> 79158
<INVESTMENTS-AT-VALUE> 77702
<RECEIVABLES> 1539
<ASSETS-OTHER> 84
<OTHER-ITEMS-ASSETS> 7
<TOTAL-ASSETS> 79332
<PAYABLE-FOR-SECURITIES> 0
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 243
<TOTAL-LIABILITIES> 243
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 79961
<SHARES-COMMON-STOCK> 669<F1>
<SHARES-COMMON-PRIOR> 320<F1>
<ACCUMULATED-NII-CURRENT> 0
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> 584
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> (1456)
<NET-ASSETS> 4286<F1>
<DIVIDEND-INCOME> 0
<INTEREST-INCOME> 241<F1>
<OTHER-INCOME> 0
<EXPENSES-NET> (77)<F1>
<NET-INVESTMENT-INCOME> 164<F1>
<REALIZED-GAINS-CURRENT> 968
<APPREC-INCREASE-CURRENT> (8038)
<NET-CHANGE-FROM-OPS> (3158)
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> (164)<F1>
<DISTRIBUTIONS-OF-GAINS> (100)<F1>
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 652<F1>
<NUMBER-OF-SHARES-REDEEMED> (325)<F1>
<SHARES-REINVESTED> 22<F1>
<NET-CHANGE-IN-ASSETS> (10735)
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> 2480
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 22<F1>
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 77<F1>
<AVERAGE-NET-ASSETS> 4487<F1>
<PER-SHARE-NAV-BEGIN> 7.19<F1>
<PER-SHARE-NII> .25<F1>
<PER-SHARE-GAIN-APPREC> (.56)<F1>
<PER-SHARE-DIVIDEND> (.25)<F1>
<PER-SHARE-DISTRIBUTIONS> (.23)<F1>
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 6.40<F1>
<EXPENSE-RATIO> 1.72<F1>
[AVG-DEBT-OUTSTANDING] 0
[AVG-DEBT-PER-SHARE] 0
<FN>
<F1>Class D only. All other data are fund level.
</FN>
</TABLE>
WARNING: THE EDGAR SYSTEM ENCOUNTERED ERROR(S) WHILE PROCESSING THIS SCHEDULE.
<TABLE> <S> <C>
<ARTICLE> 6
<SERIES>
<NUMBER>051
<NAME> SELIGMAN MUNICIPAL SERIES TRUST-FLORIDA CL A
<MULTIPLIER> 1000
<S> <C>
<PERIOD-TYPE> 12-MOS
<FISCAL-YEAR-END> SEP-30-1999
<PERIOD-END> SEP-30-1999
<INVESTMENTS-AT-COST> 40819
<INVESTMENTS-AT-VALUE> 40393
<RECEIVABLES> 1106
<ASSETS-OTHER> 69
<OTHER-ITEMS-ASSETS> 5
<TOTAL-ASSETS> 41573
<PAYABLE-FOR-SECURITIES> 1743
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 128
<TOTAL-LIABILITIES> 1871
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 39901
<SHARES-COMMON-STOCK> 5072<F1>
<SHARES-COMMON-PRIOR> 5265<F1>
<ACCUMULATED-NII-CURRENT> 0
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> 227
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> (426)
<NET-ASSETS> 37606<F1>
<DIVIDEND-INCOME> 0
<INTEREST-INCOME> 2287<F1>
<OTHER-INCOME> 0
<EXPENSES-NET> (434)<F1>
<NET-INVESTMENT-INCOME> 1853<F1>
<REALIZED-GAINS-CURRENT> 232
<APPREC-INCREASE-CURRENT> (3636)
<NET-CHANGE-FROM-OPS> (1468)
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> (1853)<F1>
<DISTRIBUTIONS-OF-GAINS> (273)<F1>
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 827<F1>
<NUMBER-OF-SHARES-REDEEMED> (1128)<F1>
<SHARES-REINVESTED> 108<F1>
<NET-CHANGE-IN-ASSETS> (4701)
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> 282
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 211<F1>
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 434<F1>
<AVERAGE-NET-ASSETS> 42283<F1>
<PER-SHARE-NAV-BEGIN> 8.07<F1>
<PER-SHARE-NII> .34<F1>
<PER-SHARE-GAIN-APPREC> (.61)<F1>
<PER-SHARE-DIVIDEND> (.34)<F1>
<PER-SHARE-DISTRIBUTIONS> (.05)<F1>
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 7.41<F1>
<EXPENSE-RATIO> 1.03<F1>
[AVG-DEBT-OUTSTANDING] 0
[AVG-DEBT-PER-SHARE] 0
<FN>
<F1>Class A only. All other data are fund level.
</FN>
</TABLE>
WARNING: THE EDGAR SYSTEM ENCOUNTERED ERROR(S) WHILE PROCESSING THIS SCHEDULE.
<TABLE> <S> <C>
<ARTICLE> 6
<SERIES>
<NUMBER>053
<NAME> SELIGMAN MUNICIPAL SERIES TRUST-FLORIDA CL C
<MULTIPLIER> 1000
<S> <C>
<PERIOD-TYPE> 12-MOS
<FISCAL-YEAR-END> SEP-30-1999
<PERIOD-END> SEP-30-1999
<INVESTMENTS-AT-COST> 40819
<INVESTMENTS-AT-VALUE> 40393
<RECEIVABLES> 1106
<ASSETS-OTHER> 69
<OTHER-ITEMS-ASSETS> 5
<TOTAL-ASSETS> 41573
<PAYABLE-FOR-SECURITIES> 1743
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 128
<TOTAL-LIABILITIES> 1871
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 39901
<SHARES-COMMON-STOCK> 34<F1>
<SHARES-COMMON-PRIOR> 0<F1>
<ACCUMULATED-NII-CURRENT> 0
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> 227
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> (426)
<NET-ASSETS> 253<F1>
<DIVIDEND-INCOME> 0
<INTEREST-INCOME> 4<F1>
<OTHER-INCOME> 0
<EXPENSES-NET> (1)<F1>
<NET-INVESTMENT-INCOME> 3<F1>
<REALIZED-GAINS-CURRENT> 232
<APPREC-INCREASE-CURRENT> (3636)
<NET-CHANGE-FROM-OPS> (1468)
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> 3<F1>
<DISTRIBUTIONS-OF-GAINS> 0<F1>
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 34<F1>
<NUMBER-OF-SHARES-REDEEMED> 0<F1>
<SHARES-REINVESTED> 0<F1>
<NET-CHANGE-IN-ASSETS> (4701)
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> 282
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 0<F1>
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 1<F1>
<AVERAGE-NET-ASSETS> 208<F1>
<PER-SHARE-NAV-BEGIN> 7.83<F1>
<PER-SHARE-NII> .10<F1>
<PER-SHARE-GAIN-APPREC> (.40)<F1>
<PER-SHARE-DIVIDEND> (.10)<F1>
<PER-SHARE-DISTRIBUTIONS> 0<F1>
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 7.43<F1>
<EXPENSE-RATIO> 1.78<F1>
[AVG-DEBT-OUTSTANDING] 0
[AVG-DEBT-PER-SHARE] 0
<FN>
<F1>Class C only. All other data are fund level.
</FN>
</TABLE>
WARNING: THE EDGAR SYSTEM ENCOUNTERED ERROR(S) WHILE PROCESSING THIS SCHEDULE.
<TABLE> <S> <C>
<ARTICLE> 6
<SERIES>
<NUMBER>054
<NAME> SELIGMAN MUNICIPAL SERIES TRUST-FLORIDA CL D
<MULTIPLIER> 1000
<S> <C>
<PERIOD-TYPE> 12-MOS
<FISCAL-YEAR-END> SEP-30-1999
<PERIOD-END> SEP-30-1999
<INVESTMENTS-AT-COST> 40819
<INVESTMENTS-AT-VALUE> 40393
<RECEIVABLES> 1106
<ASSETS-OTHER> 69
<OTHER-ITEMS-ASSETS> 5
<TOTAL-ASSETS> 41573
<PAYABLE-FOR-SECURITIES> 1743
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 128
<TOTAL-LIABILITIES> 1871
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 39901
<SHARES-COMMON-STOCK> 248<F1>
<SHARES-COMMON-PRIOR> 240<F1>
<ACCUMULATED-NII-CURRENT> 0
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> 227
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> (426)
<NET-ASSETS> 1843<F1>
<DIVIDEND-INCOME> 0
<INTEREST-INCOME> 119<F1>
<OTHER-INCOME> 0
<EXPENSES-NET> (39)<F1>
<NET-INVESTMENT-INCOME> 80<F1>
<REALIZED-GAINS-CURRENT> 232
<APPREC-INCREASE-CURRENT> (3636)
<NET-CHANGE-FROM-OPS> (1468)
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> (80)<F1>
<DISTRIBUTIONS-OF-GAINS> (14)<F1>
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 121<F1>
<NUMBER-OF-SHARES-REDEEMED> (119)<F1>
<SHARES-REINVESTED> 6<F1>
<NET-CHANGE-IN-ASSETS> (4701)
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> 282
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 11<F1>
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 39<F1>
<AVERAGE-NET-ASSETS> 2193<F1>
<PER-SHARE-NAV-BEGIN> 8.08<F1>
<PER-SHARE-NII> .28<F1>
<PER-SHARE-GAIN-APPREC> (.60)<F1>
<PER-SHARE-DIVIDEND> (.28)<F1>
<PER-SHARE-DISTRIBUTIONS> (.05)<F1>
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 7.43<F1>
<EXPENSE-RATIO> 1.78<F1>
[AVG-DEBT-OUTSTANDING] 0
[AVG-DEBT-PER-SHARE] 0
<FN>
<F1>Class D only. All other data are fund level.
</FN>
</TABLE>
WARNING: THE EDGAR SYSTEM ENCOUNTERED ERROR(S) WHILE PROCESSING THIS SCHEDULE.
<TABLE> <S> <C>
<ARTICLE> 6
<SERIES>
<NUMBER>041
<NAME> SELIGMAN MUNICIPAL SERIES TRUST-NORTH CAROLINA CL A
<MULTIPLIER> 1000
<S> <C>
<PERIOD-TYPE> 12-MOS
<FISCAL-YEAR-END> SEP-30-1999
<PERIOD-END> SEP-30-1999
<INVESTMENTS-AT-COST> 28588
<INVESTMENTS-AT-VALUE> 28423
<RECEIVABLES> 439
<ASSETS-OTHER> 149
<OTHER-ITEMS-ASSETS> 7
<TOTAL-ASSETS> 29018
<PAYABLE-FOR-SECURITIES> 0
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 101
<TOTAL-LIABILITIES> 101
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 28917
<SHARES-COMMON-STOCK> 3586<F1>
<SHARES-COMMON-PRIOR> 3898<F1>
<ACCUMULATED-NII-CURRENT> 0
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> 247
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> (165)
<NET-ASSETS> 27224<F1>
<DIVIDEND-INCOME> 0
<INTEREST-INCOME> 1667<F1>
<OTHER-INCOME> 0
<EXPENSES-NET> (326)<F1>
<NET-INVESTMENT-INCOME> 1341<F1>
<REALIZED-GAINS-CURRENT> 254
<APPREC-INCREASE-CURRENT> (2615)
<NET-CHANGE-FROM-OPS> (962)
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> (1341)<F1>
<DISTRIBUTIONS-OF-GAINS> (452)<F1>
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 202<F1>
<NUMBER-OF-SHARES-REDEEMED> (643)<F1>
<SHARES-REINVESTED> 129<F1>
<NET-CHANGE-IN-ASSETS> (4897)
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> 466
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 153<F1>
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 326<F1>
<AVERAGE-NET-ASSETS> 30649<F1>
<PER-SHARE-NAV-BEGIN> 8.30<F1>
<PER-SHARE-NII> .35<F1>
<PER-SHARE-GAIN-APPREC> (.59)<F1>
<PER-SHARE-DIVIDEND> (.35)<F1>
<PER-SHARE-DISTRIBUTIONS> (.12)<F1>
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 7.59<F1>
<EXPENSE-RATIO> 1.06<F1>
[AVG-DEBT-OUTSTANDING] 0
[AVG-DEBT-PER-SHARE] 0
<FN>
<F1>Class A only. All other data are fund level.
</FN>
</TABLE>
WARNING: THE EDGAR SYSTEM ENCOUNTERED ERROR(S) WHILE PROCESSING THIS SCHEDULE.
<TABLE> <S> <C>
<ARTICLE> 6
<SERIES>
<NUMBER>043
<NAME> SELIGMAN MUNICIPAL SERIES TRUST-NORTH CAROLINA CL C
<MULTIPLIER> 1000
<S> <C>
<PERIOD-TYPE> 12-MOS
<FISCAL-YEAR-END> SEP-30-1999
<PERIOD-END> SEP-30-1999
<INVESTMENTS-AT-COST> 28588
<INVESTMENTS-AT-VALUE> 28423
<RECEIVABLES> 439
<ASSETS-OTHER> 149
<OTHER-ITEMS-ASSETS> 7
<TOTAL-ASSETS> 29018
<PAYABLE-FOR-SECURITIES> 0
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 101
<TOTAL-LIABILITIES> 101
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 28917
<SHARES-COMMON-STOCK> 1<F1>
<SHARES-COMMON-PRIOR> 0<F1>
<ACCUMULATED-NII-CURRENT> 0
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> 247
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> (165)
<NET-ASSETS> 10<F1>
<DIVIDEND-INCOME> 0
<INTEREST-INCOME> 0<F1>
<OTHER-INCOME> 0
<EXPENSES-NET> 0<F1>
<NET-INVESTMENT-INCOME> 0<F1>
<REALIZED-GAINS-CURRENT> 254
<APPREC-INCREASE-CURRENT> (2615)
<NET-CHANGE-FROM-OPS> (962)
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> 0<F1>
<DISTRIBUTIONS-OF-GAINS> 0<F1>
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 1<F1>
<NUMBER-OF-SHARES-REDEEMED> 0<F1>
<SHARES-REINVESTED> 0<F1>
<NET-CHANGE-IN-ASSETS> (4897)
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> 466
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 0<F1>
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 0<F1>
<AVERAGE-NET-ASSETS> 9<F1>
<PER-SHARE-NAV-BEGIN> 7.97<F1>
<PER-SHARE-NII> .10<F1>
<PER-SHARE-GAIN-APPREC> (.38)<F1>
<PER-SHARE-DIVIDEND> (.10)<F1>
<PER-SHARE-DISTRIBUTIONS> 0<F1>
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 7.59<F1>
<EXPENSE-RATIO> 1.80<F1>
[AVG-DEBT-OUTSTANDING] 0
[AVG-DEBT-PER-SHARE] 0
<FN>
<F1>Class C only. All other data are fund level.
</FN>
</TABLE>
WARNING: THE EDGAR SYSTEM ENCOUNTERED ERROR(S) WHILE PROCESSING THIS SCHEDULE.
<TABLE> <S> <C>
<ARTICLE> 6
<SERIES>
<NUMBER>044
<NAME> SELIGMAN MUNICIPAL SERIES TRUST-NORTH CAROLINA CL D
<MULTIPLIER> 1000
<S> <C>
<PERIOD-TYPE> 12-MOS
<FISCAL-YEAR-END> SEP-30-1999
<PERIOD-END> SEP-30-1999
<INVESTMENTS-AT-COST> 28588
<INVESTMENTS-AT-VALUE> 28423
<RECEIVABLES> 439
<ASSETS-OTHER> 149
<OTHER-ITEMS-ASSETS> 7
<TOTAL-ASSETS> 29018
<PAYABLE-FOR-SECURITIES> 0
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 101
<TOTAL-LIABILITIES> 101
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 28917
<SHARES-COMMON-STOCK> 222<F1>
<SHARES-COMMON-PRIOR> 176<F1>
<ACCUMULATED-NII-CURRENT> 0
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> 247
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> (165)
<NET-ASSETS> 1683<F1>
<DIVIDEND-INCOME> 0
<INTEREST-INCOME> 87<F1>
<OTHER-INCOME> 0
<EXPENSES-NET> (29)<F1>
<NET-INVESTMENT-INCOME> 58<F1>
<REALIZED-GAINS-CURRENT> 254
<APPREC-INCREASE-CURRENT> (2615)
<NET-CHANGE-FROM-OPS> (962)
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> (58)<F1>
<DISTRIBUTIONS-OF-GAINS> (21)<F1>
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 59<F1>
<NUMBER-OF-SHARES-REDEEMED> (21)<F1>
<SHARES-REINVESTED> 8<F1>
<NET-CHANGE-IN-ASSETS> (4897)
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> 466
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 8<F1>
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 29<F1>
<AVERAGE-NET-ASSETS> 1597<F1>
<PER-SHARE-NAV-BEGIN> 8.30<F1>
<PER-SHARE-NII> .29<F1>
<PER-SHARE-GAIN-APPREC> (.59)<F1>
<PER-SHARE-DIVIDEND> (.29)<F1>
<PER-SHARE-DISTRIBUTIONS> (.12)<F1>
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 7.59<F1>
<EXPENSE-RATIO> 1.81<F1>
[AVG-DEBT-OUTSTANDING] 0
[AVG-DEBT-PER-SHARE] 0
<FN>
<F1>Class D only. All other data are fund level.
</FN>
</TABLE>
INDEPENDENT AUDITORS' REPORT
The Board of Trustees
Seligman Municipal Series Trust
In planning and performing our audit of the financial statements of Seligman
Municipal Series Trust (the "Company") (including the California High Yield,
California Quality, Florida and North Carolina Series) for the year ended
September 30, 1999 (on which we have issued our report dated November 5, 1999),
we considered its internal control, including control activities for
safeguarding securities, in order to determine our auditing procedures for the
purpose of expressing our opinion on the financial statements and to comply with
the requirements of Form N-SAR, and not to provide assurance on the Company's
internal control.
The management of the Company is responsible for establishing and maintaining
internal control. In fulfilling this responsibility, estimates and judgments by
management are required to assess the expected benefits and related costs of
controls. Generally, controls that are relevant to an audit pertain to the
entity's objective of preparing financial statements for external purposes that
are fairly presented in conformity with generally accepted accounting
principles. Those controls include the safeguarding of assets against
unauthorized acquisition, use, or disposition.
Because of inherent limitations in any internal control, misstatements due to
error or fraud may occur and not be detected. Also, projections of any
evaluation of internal control to future periods are subject to the risk that
the internal control may be become inadequate because of changes in conditions
or that the degree of compliance with policies and procedures may deteriorate.
Our consideration of the Company's internal control would not necessarily
disclose all matters in internal control that might be material weaknesses under
standards established by the American Institute of Certified Public Accountants.
A material weakness is a condition in which the design or operation of one or
more of the internal control components does not reduce to a relatively low
level the risk that misstatements caused by error or fraud in amounts that would
be material in relation to the financial statements being audited may occur and
not be detected within a timely period by employees in the normal course of
performing their assigned functions. However, we noted no matters involving the
Company's internal control and its operation, including controls for
safeguarding securities, that we consider to be material weaknesses as defined
above as of September 30, 1999.
This report is intended solely for the information and use of management, and
the Board of Trustees of Seligman Municipal Series Trust, and the Securities and
Exchange Commission and is not intended to be and should not be used by anyone
other than these specified parties.
s/sDELOITTE & TOUCHE LLP
- ------------------------
DELOITTE & TOUCHE LLP
New York, New York
November 5, 1999
