Correction Appended

Proust had his madeleines. Douglas Boxer had his Mallomars.

"My mother used to buy them on special occasions, and I used to sneak down to the kitchen and steal them," said Mr. Boxer, who grew up to be an owner of Rare Bar & Grill, a restaurant in the Shelburne Murray Hill Hotel at 303 Lexington Avenue, near 37th Street. "And then she'd say, 'Somebody last night had three Mallomars. Wonder who it was?' "

That question comes up at this time of year, for like Beaujolais nouveau, Mallomars are not a year-round delicacy, not even in the New York area, where 70 percent of Mallomars are sold. Mallomars return to supermarket shelves in the fall after a warm-weather break. But Mallomars connoisseurs do not celebrate by holding tastings of the new batch or by calling friends to announce "les Mallomars sont arrivés."

There are those who say that Mallomars fans just don't want to share that first bite of the season, a bite "so fresh it would crunch," said Jodi Gray Kahn, an English teacher at Great Neck North High School on Long Island. To hear her tell it, her father seemed to enjoy the first-bite moment even more than she did.

So now is as good a time as any to investigate this New York-area phenomenon, the arrival of the beloved Mallomars, and to plumb some of their mysteries: Why do they melt in hot weather when science has come up with ways to keep pretty much anything from melting? Does the answer, whatever it is, have anything to do with the fact that this cookie, born in New Jersey, is now made in Canada? And what about the Whippet, a Canadian cookie that is about the same size and shape, but packs more calories, more carbohydrates and more sugar?