Tortoise

Tortoises ( /ˈtɔːr.təs.ɪz/, Testudinidae) are a family of land-dwelling reptiles in the orderTestudines. Like their marine cousins, the sea turtles, tortoises are shielded from predatorsby a shell. The top part of the shell is the carapace, the underside is the plastron, and the two are connected by the bridge. The tortoise has an endoskeleton with an adaptation of having an external shell fused to the ribcage. Tortoises can vary in size from a few centimeters to two meters. Tortoises are usually diurnal animals with tendencies to becrepuscular depending on the ambient temperatures. They are generally reclusive animals.

http://en.wikipedia.org/wiki/Tortoise