164 CLASS REPTILIA. 



But among the fossils of ancient calcareous formations, there exist two 

 genera, far more extraordinary, and which, with the head and trunk of a 

 Saurian, have feet supported on short members, and formed of a multitude 

 of small articulations, assembled in a kind of oar or fin, like the paddles or 

 fore-feet of the cetacea. 



One of these genera, the Ichthyosaurus, had a large head, on a neck 

 rather short, enormous ej'es, a moderate tail, an elongated muzzle armed with 

 conical teeth, adhering in a groove. Different species have been discovered 

 in England, France, and Germany, some of which are very large. 



The other, the Plesiosaurus, had a small head, supported on a long, 

 serpent-like neck, composed of more conical vertebrse than in any known 

 animal. Its tail was short. Debris of it have been also found on the 

 continent. 



These two genera, the discovery of which is mainly owing to the 

 researches of Sir Everard Home, Mr. Conybeare, Dr. Buckland, &c., inha- 

 bited the sea. They should form a verj^ distinct family ; but from what is 

 known of their osteology, they approach more to the common Saurians 

 than to the crocodiles, to which M. Fitzinger associates them in his family 

 of LoRTCATA, which allocation is so much the more gratuitous, as we are 

 neither acquainted with their scales, nor tongue, the two characteristic 

 parts of the Loricata. 



