Small stocks dragged under the weight of the larger selloff Thursday despite a fair amount of positive earnings news.

Video-systems maker Vicon Industries ( VII) was among the winners, soaring 19% to $9.80 after the Hauppauge, N.Y., company swung to a fiscal second-quarter profit of $802,000, or 16 cents a share.

Virginia-based Versar ( VSR), an infrastructure-program-management company, surged 26% to $6.60 after fiscal third-quarter earnings more than tripled from last year to 36 cents a share. Revenue more than doubled.

Elsewhere in earnings news, Inter Parfums ( IPAR) added 13.4% to $27.09 in far-heavier-than-usual trading after the New York-based fragrance maker beat the first-quarter per-share earnings consensus of 23 cents by a nickel a share.

Air Methods ( AIRM), of Colorado, jumped 15% to $32.88 after earning 30 cents a share in the first quarter, which trounced two analysts' 11-cent targets. And Sacramento, Calif., renewable-fuels maker Pacific Ethanol ( PEIX) squared with bottom-line estimates, lifting shares by 9% to $15.09.

Away from earnings, Torch Energy Royalty Trust ( TRU), based in Delaware, surged 26% to $8.02 after Trust Venture Co. launched an $8 per-unit tender offer for all of Torch's outstanding units.

Heavily on the downswing, however, was Tweeter Home Entertainment ( TWTR). Shares tanked 69.6% to 41 cents in very heavy trading after the Canton, Mass., electronics retailer reported swinging to a wide loss for the quarter ended March 31 -- $35.2 million, or $1.38 a share -- and said it might have to file for bankruptcy due to its precarious financial situation.

Shares of Pope & Talbot ( POP) lost nearly a third of their value after the Oregon-based maker of paper and wood products reported it had widened its first-quarter loss to $18.6 million, or $1.15 a share, from 49 cents last year. Revenue, at $200.5 million, represents a decline from last year and falls short of two analysts' estimates.

Business-services firm Metretek Technologies ( MEK) widely missed on both first-quarter income and revenue, and Ohio's Core Molding Technologies ( CMT), which makes fiberglass/carbon reinforced plastics, halved its earnings from last year to 11 cents a share. Denver-based Meretek plunged 19.3% to $11.30; Core Molding lost 13% at $7.15.

Finally, Seattle-based biotech Dendreon ( DNDN) was hurting again, giving up another 12.5% to $5.54 on a downgrade to sell by Banc of America following Wednesday's harrowing free fall. The company also reported that its first-quarter loss widened to $30.9 million, or 38 cents a share, from 34 cents a share last year.

The Russell 2000, which harbors Dendreon, was off 16.14 points, or 1.9%, at 818.63. The S&P SmallCap 600 surrendered 1.8% to 425.69.

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