Calyptra
the hood of the theca or capsule of mosses. The same name is given to any hood-like body connected with the organs of fructification in flowering plants. It CALYPTRÆA, a genus of gasteropods, furnished with a patelliform shell, to the cavity of which a smaller conical one adheres, like a cup in a saucer. is the typical genus of the family Calyptræidæ. The species are called cup-andsaucer limpets.