ORDER CROCODILIA. 



93 



premaxillae ; the supratemporal fossae are of somewhat large size, 

 and sometimes exceed the orbits in this respect ; while the mandi- 

 bular symphysis is very long, and embraces the anterior portion of 

 the splenial bone. The teeth are always numerous, and are only 

 slightly unequal in size ; and neither of the existing species is pro- 

 vided with a ventral armour. In this group Rhamphosuchas, of the 

 Pliocene of the Siwalik Hills of India, was a gigantic form probably 

 between fifty and sixty feet in length, and characterised by the stout- 

 ness of the teeth, of which the upper series bites on the outer side 

 of the lower, as in the Alligators, instead of interlocking with them 

 as in other members of this group. In Thoracosaurus, again, of 

 the Cretaceous of North America, we have a genus remarkable for 

 retaining the preorbital vacuity of the Teleosauridce, and in having 

 the supratemporal fossa larger than the orbit ; 

 both these features apparently pointing to the 

 direct descent of this genus from the last-named 

 family, without having passed through the inter- 

 mediate stage of the Goniopholididcz. The exist- 

 ing Indian Garialis gangeticus, of which the den- 

 tal succession is shown in fig. 1090, is one of the 

 existing species of Reptiles of which remains are 

 found in the Pliocene of the Siwalik Hills. The 

 same deposits have also yielded two more or less 

 nearly allied extinct species ; while in the some- 

 what older beds of Sind there occur two other 

 species differing considerably in the form of the 

 orbit and other cranial characters from the existing 

 representative of the genus. One of these extinct 

 species (G. pachyrhy fichus) appears to have attained 

 dimensions fully equal to those of Rhcwiphosuchus. 

 Another Gharialoid provisionally referred to the 

 present genus occurs in the Middle Eocene of 

 Bracklesham, in Sussex ; while species from the 

 Cretaceous of North America, which have been 

 described under the generic name of Ho/ops, may 

 prove to be allied either to the present or to the 

 next genus. In Tomistoma, typically represented 

 by the existing T. Schlegeli of Borneo, may be in- 

 cluded the fossil forms described under the names 

 of Melitosaurus and Garialosuchus (fig. 1091). 

 readily distinguished from Garialis by the circumstance that the 

 nasals extend forwards to articulate with the premaxillae (fig. 1091), 

 instead of being separated from them by a long interval. A large 

 fossil form (Melitosaurus) occurs in the Miocene of Malta, and a 

 smaller (Garialosuchus) in that of Austria. Another Gharialoid, 



Fig. 1090. — Teeth 

 of Garialis gangeti- 

 cus, showing succes- 

 sion of germs {b, c) 

 beneath the tooth in 

 use(a). (After Owen.) 



This 



genus is 



