SAURIANS. 481 



resembles the living Saurians in the general contour of the head 

 and jaws, but differs from them widely in the conformation of the 

 muzzle, and the opening of the nose. Many species of the fossil 

 Crocodiles were of enormous size, much larger than the living 

 ones of the present day. 



SUB-FAMILY. MARINE FOSSIL LIZARDS. 



Enaliosauria, (Gr. sv&hog, enalios, marine; crai5^o?, sauros, a 



lizard.) 



This group includes some very extraordinary fossil Saurians. 

 Little else than the bones have been preserved, and from these 

 alone the structure and habits are inferred. It is hence impos- 

 sible to speak with certainty in regard to many parts of the living 

 organization ; while yet it is made quite clear, that in these ex- 

 tinct and gigantic reptiles, the extremities were flattened into 

 fin-like flippers, connecting them with the CHELONIA, and, to- 

 gether with other peculiarities of their structure, pointing out the 

 animals as exclusively aquatic. The Enaliosaurians " inhabited 

 the seas of Europe during the Trias and Jura formations." We 

 are not aware that any species have as yet been discovered in 

 North America. The two genera, are, 



1st, Ichthyosaurus, (Gr. ichthus, a fish; sauros, a lizard.) 

 (See Chart.) This reptile is, according to Prof. Owen, a singu- 

 lar compound, in which the characters of the fish, the cetacea, 

 and the bird are engrafted upon an essentially Saurine type of 

 structure. Dr. Buckland, in his "Bridgewater Treatise," says 

 of it, "It presents combinations of form and mechanical con- 

 trivances, which are now dispersed through various classes and 

 orders of existing animals, but are no longer united in the same 

 genus. Thus, in the same individual, the snout of a Porpoise 

 is combined with the teeth of a Crocodile ; the head of a Lizard 

 with the vertebrae of a Fish ; and the sternum of the Orni- 

 thorhyncus with the paddles of a Whale." The general outline 

 of an Ichthyosaurus "must have most nearly resembled the 

 modern Porpoise or Grampus. It had four broad feet or paddles, 

 and terminated behind in a long and powerful tail." The struct- 

 ure of the skeleton is like that of a Saurian ; but the vertebral 

 column consists of more than a hundred vertebrae, each of which 

 is hollow, and fashioned like those of fishes. The form of the 

 sternal arch and the broad surfaces of the clavicles are adapted 

 to give great strength to the chest, and enable the animal to 

 breast the most disturbed waters. Dr. Buckland remarks, that 

 " the bones composing the arch are combined nearly in the same 



