THE WASHINGTON POST Thitrstlny, Mny l*K l*WÛ÷i  
NEW YORK, May 18ÛÓA late round of selling in blue chips blunted an early rally in the stock market today, leaving prices mixed after a busy session.</br></br>Selling pressure was evident in such market leaders as International Business Machines, General Electric and General Motors, as well as the oil group. But some retailing issues were strong.</br></br>The Dow Jones average of 30 industrials, up about 14 points at midday, was off 2.23 points at 1,203.56 by the close.</br></br>Evidence has been accumulating in recent days that the recovery from the recession is gaining momentum. As the market opened this morning, the government reported that personal income rose a seasonally adjusted 0.8 percent in April from the month before, for its biggest increase since last July.</br></br>In the last two hours of the session, however, sellers took over, wiping out most of the early gains in stock prices. Merrill Lynch was reported to be handling a long list of sell orders from a single investing institution.