Fashion: Only the Young

As the showings wound up in Paris last week, the question seemed to be: What do you wear if you are over 20? To emphasize the point, Yves St. Lau rent sent his models out with their hair done up in little-girl braids or little-boy helmets. The colors were as gay as a picture book; in fact, that is where the idea came from, St. Laurent explained. His mother gave him a book of Mondrian's paintings just last Christmas, and his showstoppers were all movable Mondrians, practically gift-wrapped: jersey dresses splashed with...