Wall Street extended its fourth-quarter rally into a second day Monday, supported by falling oil prices and a bullish assessment of the economy from a Federal Reserve official.

Investors were cheered by a dip in oil prices, which backed off the $50-per-barrel mark of Friday's close of trading. A barrel of light crude closed at $49.91, down 21 cents, on the New York Mercantile Exchange.

Stocks received a boost before the session opened when Philadelphia Federal Reserve President Anthony M. Santomero said in a speech that he expected the economy to grow by 3.5 percent to 4 percent through 2005. His comments and the buying that customarily opens a new quarter gave stocks their gains, although analysts said recent economic data and the forecast for third-quarter earnings might not support the bullishness.

The Dow Jones industrial average rose 23.89, or 0.2 percent, to 10,216.54. The Standard & Poor's 500-stock index gained 3.67, or 0.3 percent, to 1135.17. The Nasdaq composite index advanced 10.20, or 0.5 percent, to 1952.40.

Dow component American International Group, one of the world's largest insurance firms, slipped 23 cents, to $68.49, after it announced the Securities and Exchange Commission may sue the company for alleged violations of federal securities laws, based on allegedly misleading statements AIG made in recent news releases.

Wal-Mart Stores, the closely watched bellwether for the retail sector, pleased investors as it announced that sales at its stores open at least a year rose 2.3 percent in September, somewhat making up for a disappointing August. While sales fell compared with a year ago, investors saw the increase as a plus, especially considering the recent lack of consumer spending. Wal-Mart rose 18 cents, to $53.31.

Office Depot gained 6 cents, to $15.14, after it announced that its chairman and chief executive, Bruce Nelson, resigned his post after reaching an agreement with the company's board of directors.

Charles Schwab Corp. fell 15 cents, to $9.07, after its brokerage subsidiary said it would reduce commissions for its online trading customers.

Other Indicators

* The New York Stock Exchange composite index rose 14.57, to 6677.75; the American Stock Exchange index fell 2.93, to 1276.34; and the Russell 2000 index of smaller-company stocks rose 4.06, to 589.09.

* Advancing issues outnumbered declining ones by 3 to 2 on the NYSE and the Nasdaq Stock Market. NYSE trading volume fell to 1.53 billion shares, from 1.58 billion on Friday, and Nasdaq volume totaled 1.83 billion, up from 1.81 billion.

* The price of the Treasury's 10-year note rose $1.25 per $1,000 invested, and its yield fell to 4.17 percent, from 4.19 percent on Friday.

* The dollar rose against the Japanese yen and the euro. In late New York trading, a dollar bought 110.87 yen, up from 110.40 late Friday, and a euro bought $1.2287, down from $1.2407.

* Gold for current delivery fell to $414.00 a troy ounce, from $419.50 on Friday, on the New York Mercantile Exchange's Commodity Exchange.