DRAGON SHELL, in Natural History, a name given by some to a species of conchiferous patella or limpet. This has a top very much bent; and is of an ash colour on the outside, but of an elegant and bright flesh colour within. This has been found sticking on the back of a tortoise, as the common limpets do on the sides of rocks; and some have been found affixed to large shells of the pinna marina brought from the East Indies at different times.