On the margins of Chaleur Bay on Quebec's Gasp,e Peninsula are found remarkable stones whose patterns suggest moons and sunsets, wind and water, growth and movement, the glacial passage of time. Or so it seemed to artist Harold Weston, whose series of ink-wash paintings based on 14 of the stones opens Saturday at the Phillips Collection.

For the last five years before his death in 1972, Weston turned from landscapes and nudes to capture the rocks' inner essence and outer contours, their black-and-white ovals, striations and spirals. In his earlier years Weston said he could see the woods and mountains in his nudes; it's possible to see nudes, nature and the dominion of space in his colorful rock-based works, which grew progressively abstract toward the end. (The rocks remain, and are on view, too.)

Opening simultaneously is a retrospective of works by Phillips curator James McLaughlin, who was organizing the Weston show at the time of his death. McLaughlin's still lifes are tranquil, intimate studies of simple sensory pleasures. Anemones, a barn, "Glass, Fish and Plate," an owl, an egg, a woman "After the Bath" -- the subjects and textures recall those of the French impressionists in the museum's collection. Four small works hang in the tiny downstairs vestibule, showing rich, muted tones in the natural light.

The Phillips was McLaughlin's domain for more than 40 years, and the paintings seem more at home there than have some of the gallery's rowdier recent shows. The catalogue contains memorial appreciations by friends and colleagues. Together the shows are soothing summer replacements while the museum's masterworks are on the road.

HAROLD WESTON: THE STONE SERIES -- At the Phillips Collection through July 18.