Small-cap stocks spent much of Monday on the losing side, falling harder than the broader market. The Russell 2000 dropped 1.9% to 647.88, and the S&P SmallCap 600 lost 1.5% to 346.92.

Leading the downward charge was CRA International ( CRAI). Shares of the Boston-based economic, financial and management consulting company plummeted 40% on Friday evening's first-quarter earnings forecast. CRA expects earnings per share between 26 cents and 28 cents on revenue of $86 million. Analysts polled by Thomson Financial are looking for 58 cents a share on revenue of $92.5 million. This morning, Stifel Nicolaus downgraded the stock to hold from buy.

Curis ( CRIS), a drug discovery and development firm based in Cambridge, Mass., likewise took a pounding, down 19% to $1.16. Wyeth ( WYE), a large biotech firm, will no longer collaborate with Curis on its Hedgehog agonist program, which attempts to develop treatments for stroke and cardiovascular indications. Large-cap Wyeth was also , down trading 2.8% lower at $40.15.

Houston, Texas' ExpressJet ( XJT), which operates as the Continental Express airline, saw shares tumble 15.3% to $1.89 on fourth-quarter earnings. Excluding charges, the company reported a loss of $27.6 million, or 52 cents a share, vs. a profit of $22.8 million, or 39 cents a share, in 2006. The Street was looking for a loss of 30 cents a share.

On the winning side, shares of Art Technology ( ARTG), a Cambridge, Mass.-based maker of e-commerce software, gained 16% to $3.26. Roth Capital had upgraded the company to buy from hold before the open.

Finally, San Diego-based Iomega ( IOM), which manufactures portable data storage products, got a buyout offer from EMC ( EMC). Iomega said its board had unanimously determined that EMC's unsolicited bid of $3.25 a share did not constitute a superior offer to a previously agreed-upon all-stock transaction with Iomega stockholder Great Wall Technology. Iomega shares climbed 20% to $3.20. EMC traded down