Shares of Legg Mason ( LM - Get Report) were among the NYSE's losers Wednesday, tumbling 17% after the asset manager warned that second-quarter earnings will be weaker than expected.

For the period ended Sept. 30, the company expects to report earnings of $138 million to $148 million, or 96 cents to $1.02 a share. Analysts polled by Thomson First Call project earnings of $1.16 a share. Legg Mason blamed the shortfall on lower-than-expected revenue and about $12 million in unanticipated mutual fund distribution fee expenses. Shares were trading down $18.30 to $87.01.

Alcoa ( AA - Get Report) slid 6% after the aluminum producer posted disappointing third-quarter results. The company posted earnings from continuing operations of $540 million, or 62 cents a share, on revenue of $7.63 billion. Analysts expected earnings of 77 cents a share on revenue of $7.75 billion. During the year-earlier period, Alcoa earned $285 million, or 33 cents a share, on revenue of $6.4 billion. Shares were trading down $1.62 to $26.67.

Shares of Gannett ( GCI - Get Report) fell 2% after the newspaper publisher posted in-line third-quarter earnings but reported weak revenue. Gannett's earnings fell to $261.4 million, or $1.11 a share, from $297 million, or $1.22 a share a year earlier. The results matched analysts' mean estimate. Excluding stock option cost of $6.4 million, or 3 cents a share, earnings would have been above last year's third quarter results.

Gannett's revenue increased to $1.91 billion from $1.86 billion, shy of Wall Street's forecast of $1.94 billion. Newspaper ad revenue dropped 1.2% on a pro forma basis in the third quarter, and 3.2% in September. Shares were down $1.28 to $56.44.

Monsanto ( MON) fell 7% after the agricultural products company posted an in-line fourth-quarter loss but issued a fiscal 2007 earnings guidance below expectations. The company reported a loss of $144 million, or 27 cents a share, on revenue of $1.39 billion. Excluding discontinued operations and tax-related items, Monsanto posted a loss of 21 cents a share. Analysts anticipated a loss of 21 cents a share and revenue $1.34 billion. A year earlier, the company reported a loss of $125 million, or 23 cents a share, on revenue of $1.27 billion.

For fiscal 2007, Monsanto predicts earnings of $1.50 to $1.57 a share. Analysts project earnings of $1.62 a share. Shares were trading down $3.03 to $43.38.

Shares of Celadon Group ( CLDN) rose modestly after the trucking company put first-quarter earnings above Wall Street's estimate. For the period ended Sept. 30, the company expects to post earnings of 28 cents to 30 cents a share. Analysts project earnings of 26 cents a share. Shares were adding 8 cents to $19.71.

Shares of Fastenal ( FAST - Get Report) rose 2% after the industrial and construction supplies company posted third-quarter earnings that topped forecasts. The company earned $54.1 million, or 36 cents a share, up from $46 million, or 30 cents a share, a year earlier. Revenue rose to $470.1 million from $402.2 million. Analysts expected earnings of 35 cents a share and revenue of $470.8 million. Shares recently changed hands at $41.18, up 72 cents.

The NYSE's volume leaders Wednesday were Alcoa, Nortel Networks ( NT), up 2 cents to $2.18; Qwest ( Q), down 12 cents to $8.25; E*Trade ( Q), down $2.33 to $22.13; Ford ( GE), up 8 cents to $8.27; BellSouth ( BLS), up 27 cents to $43.47; AT&T ( HET), up 12 cents to $32.89; and CVS ( CVS), up $1.20 to $30.92.

Nasdaq volume leaders included Intel ( INTC), up 8 cents to $20.97; Sirius Satellite Radio ( SIRI), down 8 cents to $3.78; TD Ameritrade ( AMTD), down $2.06 to $17.04; Yahoo! ( YHOO), down 62 cents to $23.85; Cisco Systems ( CSCO), up 11 cents to $24.44. Oracle ( MSFT), down 1 cent to $18.73; Charles Schwab ( SCHW - Get Report), down 88 cents to $17.18; and Rambus ( RMBS - Get Report), up $2.11 to $19.39.