FOSSIL CROCODILIA. 271 



like kinds, which moved out to sea like the Crocodile of San Domingo, but which came rarely to land, 

 existed as the genera Steneosaurus and Teleosaurus. In these Crocodilia, the bodies of the vertebra? were 

 concave before and behind, or amphicoelous, and the pterygoid bones did not come into the hard palate, 

 the posterior nostrils being behind the palatine bones only, and there were two longitudinal series of 

 dorsal scutes instead of more, as in the Proccelia. This group of Amphiccelia became extinct during 

 the early days of the Proccelia. 



Mr. Hulke, F.R.S., has shown that in the Wealden and Purbeck deposits there is a fossil 

 Crocodile intermediate in its characters of skull between those of the Lias and Tertiary times. 



The next group preceded these in time, and lived and died out in the days of the vast continental 

 surfaces of the Trias. Instead of being perfectly aquatic forms, these Crocodiles were very terrestrial, 

 and the conformation of their nostrils and hard palate leads to the belief that they had no necessity to 

 drown their prey, and that they had not the peculiar method of life of the more modern groups. The 

 bodies of the vertebra? of these early Secondary kinds were amphicceloiis, but neither the palatine nor 

 the pterygoid bones were produced into plates, so as to form a hard palate and place the internal 

 nostrils far back in the mouth. Hence the outside nostrils communicated with the mouth in the front 

 part of the palate. They had two long series of keeled, joined, dorsal scutes, and in some there 

 was a ventral armour. The genus Stagonolepis is from Elgin, in Scotland; and Parasuchus from 

 India, and Belodon from Germany and North America. They have been called by Huxley 

 " Parasuchia." 



Owen, of whose classification of the fossil Crocodiles the above is a modification, has described 

 some little Crocodilia which he considers were sufficiently large to kill and devour the small Marsupial 

 Mammals of the age of the Purbeck deposits (Upper Oolite). 



Associated with the fossil Crocodilia is an order in which large and small reptiles with bi-concave 

 vertebrae have a dentition of teeth in sockets, which somewhat foreshadows the carnivorous Mammalia. 

 These Theriodontia of Professor Owen probably commenced in the Permian age, and lived in the 

 Oural region in Asia, and in North America, South Africa, and England, during one or more of 

 the geological ages down to the end of the Oolite period. 



Cope notices two species of Crocodilia from the Cretaceous formations west of the Mississippi ; one 

 eight or ten feet in length is Hyposaurus, which had sub-biconcave vertebrae and a long sub-cylindrical 

 snout; and the other was a short-headed species like the Alligator lucius. The New Jersey Cre- 

 taceous has also yielded Crocodilia of this genus Bottosaurus as well as Hyposaurus, and there is a 

 long-nosed Gavial from the same strata named Holops by Cope, and a second which is a Proccelian 

 Crocodilian, small in size, but also a Gavial. 



CLASSIFICATION OF THE ORDER CROCODILIA. 

 FAMILY CROCODILID.E Genus Crocodilus. 



GAVIALID.E ( Gavialis. 



[ Tomistoma. 



( Alligator. 



ALLIGATORIE^ Caiman. 



,i Jacare. 



