BASKETBALL—BOSTON retained a comfortable 3�-game lead in the East by winning two of three as CINCINNATI split four. PHILADELPHIA adopted two pretty waitresses as mascots and won two games in a row. But the 76ers quickly found out that beauty is no substitute for talent in the NBA when they dropped two of their next three. Last-place NEW YORK's rookies continued to impress as the Knicks won two straight for the first time this season before losing two of their next three. LOS ANGELES took three of four and moved three games ahead in the West. Second-place ST. LOUIS, playing without Bob Pettit. who strained his stomach muscles, defeated the Celtics 110-98 but lost three other games. BALTIMORE took two of three for the team's new owners (three local men bought the Bullets for $1.1 million), and SAN FRANCISCO lost three more before defeating the Lakers 109-106. It was the second victory for the Warriors in 11 games, and there were rumblings that Wilt Chamberlain was back to his bad old ways of playing for Chamberlain instead of the Warriors.