A rare avocado still-life painting by Georgia O'Keeffe, hidden away for decades in a private Cape Cod collection, sold at a Skinner's auction last week for $225,150, with fees. "Alligator Pear in White Dish," painted in 1921, was estimated by the Boston firm at $100,000 to $150,000. A traveling exhibition "Georgia O'Keeffe: Abstraction," with about 100 works dating from 1915 to the 1970s, is currently on view at DC's Phillips Collection.