any of same 40 species of slow-moving, terrestrial, herbivorous tortles, found in the old and new worlds but chiefly in africa and madagascar, tortoise have a high, domed shell, heavy elephantlike hind legs, and hard scaled forelegs,the four north american species have a brown shell, about 8-14in(20-35cm)long, and flattened forelimbs adapted for burrowing, the common, or european, tortoise has a shell about 7-10 in (18-25cm)long. most species of giant tortoise on the galapagos and other islands are now rare or extinct, one captive galapagos tortoise had a shell 4.25ft (1.3cm) long and weighed 300lbs(140kg)