Teleosaurus, a genus of fossil crocodilians of the secondary epoch established by Geof-froy, differing from the living crocodiles in having biconcave vertebras. The general form of the cranium was that of the gavials; the nostrils opened anteriorly at the end of the muzzle and posteriorly on a level with the jugal arch; the lower jaw was spoon-shaped at the end, with teeth on the sides like canines, the other teeth being small, equal, conical, and adapted for seizing a fish prey; the body was protected by larger and more solid plates, the anterior limbs were smaller, and the posterior more fin-like than in the present crocodilians. The strata which enclose their remains indicate a marine habitat. The genus has been divided by modern palaeontologists into several subgenera, as given by Pictet. In the lias is found mystriosaurus (Kaup), having a very long muzzle, flattened head, and eyes directed upward. The T. (M.) Chapman-ni (Konig), from the upper lias of Yorkshire, England, is described in the " Philosophical Transactions" of 1758; the vertebras were 64, 16 being dorsal, and the teeth about 70 in each jaw; some of the dermal plates were 3½ in. in their transverse diameter; it attained a length of about 13 ft.

The name has been generally restricted to the species found in the oolite, especially the T. Ca-domensis (fit. Geoffr.), or crocodile of Caen, from the limestone of Normandy,, This is characterized by large orbits near together, a flattened muzzle five times as long as wide, very long transverse processes of the dorsal vertebrae, and thick rectangular scales forming 10 regular series, each containing 15 or 1G; it must have attained a length of 20 ft.

Teloosaurus Cadomonsis.