FOSSIL REPTILES. 311 



were entire over a long space, nearly like the monitors and the 

 horned iguana, which would induce a conjecture that these 

 nostrils were large, and the bones of the nose not much ex- 

 tended, a circumstance which absolutely excludes the croco- 

 diles and the teguixin. 



The principal foramen for the issue of the suborbital nerve 

 is nearer the edge of the nostrils than in any known species. 



AVhatever doubts, says M. Cuvier, may subsist respecting 

 these scattered pieces, they do not in the slightest degree 

 affect the determination of the place of this animal. The head 

 fixes that irrevocably between the monitors and the iguanas. 

 But the size of the animal was enormous, in comparison of all 

 the known species of these two sub-genera. None of these, 

 perhaps, has the head longer than five inches, while the fossil 

 head approaches to four feet. 



In zoology, when the head, and particularly the teeth and 

 jaws, are given, almost all the rest may be concluded as far as 

 the essential characters are concerned. Thus, there was 

 Httle difficulty, in this case, of recognizing and classing the 

 vertebrae. 



All these vertebrae, like those of the living crocodiles, the 

 monitors, the iguanas, and, in general, most of the Saurian 

 and Ophidian reptiles, have their body concave^ in front and 

 convex behind, which distinguishes them remarkably from 

 those of the cetacea, which have it nearly plane, and still more 

 from that of fishes, where it is hollowed on both sides into a 

 concave cone. 



The anterior vertebrae have the concavity and convexity 

 much more strongly marked than the others. 



Of these vertebrae there are five sorts established on the 

 number of the apophyses. The first have an upper spinous 

 apophysis, long and compressed; a lower, terminated by a 

 concavity; four articulary, the hinder ones of which are 

 shorter, and face outwards; and two transverse apophyses, 

 bulky and short. These are the last vertebrae of the neck, and 



