Medarex Inc. (Nasdaq:MEDX), Smith & Wesson Holding Corp. (Nasdaq:SWHC) and A Power Energy Generation Systems Ltd. (Nasdaq:APWR) are among the most actively traded companies in Monday's trading among companies with market capitalizations under $1 billion.

Also included among the results: Spectrum Pharmaceuticals Inc.(Nasdaq:SPPI), Century Aluminum Co. (Nasdaq:CENX), Solarfun Power Holdings Co Ltd. (Nasdaq:SOLF), Matrixx Initiatives (Nasdaq:MTXX), Focus Media Holding Ltd. (Nasdaq:FMCN) and Monro Muffler Brake Inc. (Nasdaq:MNRO).

Here are the most actively traded companies among small caps:

		Price at 9:08 ET	Change	% Change	Volume	Year High	Year Low
MEDX	MEDAREX INC	8.83	+1.47	+20.0%	1,985.1k	10.12	3.40
SWHC	SMITH & WESSON HLDG CORP	5.80	-0.23	-3.8%	133.0k	7.52	1.53
APWR	A POWER ENERGY GENERAT SYS L	8.44	-0.06	-0.7%	23.3k	31.80	3.00
SPPI	SPECTRUM PHARMACEUTICALS INC	5.98	-0.05	-0.8%	18.2k	6.35	0.55
CENX	CENTURY ALUM CO	6.20	-0.27	-4.2%	11.6k	69.84	1.04
SOLF	SOLARFUN POWER HOLDINGS CO L	6.50	-0.15	-2.3%	9.7k	21.40	2.27
MTXX	MATRIXX INITIATIVES INC	5.46	-0.09	-1.6%	8.5k	19.74	5.41
FMCN	FOCUS MEDIA HLDG LTD	7.41	-0.02	-0.3%	7.9k	33.82	4.84
MNRO	MONRO MUFFLER BRAKE INC	23.83	+0.55	+2.4%	7.0k	29.40	14.85
FEED	AGFEED INDUSTRIES INC	5.88	-0.36	-5.8%	6.8k	15.18	0.90