Stocks endured back-and-forth trading following a rally Friday, which came in response to the Federal Reserve's decision to lower its discount rate. The Fed said Friday it stood ready to make further moves to keep credit and stock market losses from hurting the economy, but because it stopped short of a cut in the more important federal funds rate, uncertainty lingered on Wall Street about policymakers' intentions. The Fed is not scheduled to meet formally until Sept. 18, which means investors could remain jittery until then and could perhaps see drops in stock prices as a way to force the issue with the Fed.

Treasury bonds, which have rallied in recent weeks as investors fled to safe-haven securities, continued to move higher Monday. Bond prices move opposite their yields. Yields on the benchmark 10-year Treasury bond fell to 4.65 percent from 4.68 late Friday, while the shorter-duration notes such as the 3-year T bill saw yields fall sharply.

According to preliminary calculations, the Dow Jones industrials rose 42.27, or 0.32 percent, to 13,121.35, after rising nearly 100 points and also falling nearly 100.