At "American Legends," the Whitney's sample of American greats, a few landscapes really appealed to me: Edward Hopper's familiar Early Sunday Morning, 1930, which unfolds into three delighted dimensions on careful reading of its shadows; Georgia O'Keeffe, The Mountain, New Mexico, 1931, which was new to me (though of course I know that landscape palette), and seemed miraculously to be breathing, its colors shifting as sun might start to glow diffusely through thickly packed clouds passing slowly overhead; and William Eggleston, Untitled (Store Parking Lot), 1965-68, whose charm I find harder to articulate - something in the convergent lines, no doubt, but even more something about all the truncated messages, especially the oversize letters dwarfing an already oversize store, and something about day and night.