Aetna Life & Casualty's income dipped 4.1% to $265 million in the third quarter. The figure includes extraordinary tax benefits of $13 million and $10 million of capital gains. The Hartford, Conn., company said the year-ago quarter included extraordinary tax benefits of $54 million and $7.9 million of capital gains. Operating earnings rose 16% to $231 million. Earnings in its casualty-property businesses show significant improvement over last year, the company said, and their performance more than offsets lower results in group insurance operations.