THE KEPTILIAN CLASS OF THE MOSASAUK1D.E. 699 



as in all Lacertians ; it is much smaller than the pterygoid ; it 

 contributes by a smooth, wide, anterior emargination to circum- 

 scribe, posteriorly, the palato-naris, n, and has the same connexion 

 with the vomer, maxillary, and pterygoid as in Amblyrhynchus. 



In Ophidia the palatines (fig. 17, 20), besides supporting teeth, 

 have a narrow, elongate form, and seem to be a forward continuation 

 of the pterygoids. They unite by a posterior narrow squamous suture 

 with the pterygoid, 24, and send off a process from near the middle of 

 the inner surface, which unites with the presphenoid ; the anterior 

 ends have a loosish ligamentous connexion with the vomerine bones, 

 13. In every particular in which the veritable palatines of the 

 Mosasaurians differ from those of Serpents they agree with those of 

 Lizards, and of the Monitors more especially. I may here note the 

 many and characteristic vacuities in the palate of the Python (fig. 

 17); viz. the vomero-maxillary, 2, the palatonarial, n, the interpalatal, 

 the interpterygoid, s, s', and the pterygomaxillary, y. 



Cuvier, who appended views of the palate in an Iguana and a 

 Monitor to elucidate the character of that part of the skull in 

 Mosasaurus, tersely propounds the case as follows : — " Jusqu'ici 

 l'animal de Maestricht seroit done plus voisin des monitors que des 

 autres sauriens ; mais tout d'un coup nous trouvons dans ses os 

 pterygoidiens un caractere qui Ten eloigne pour le porter vers les 

 lezards proprement dits et les iguanes ; ce sont les dents dont ces os 

 sont amies qui constituent ce caractere." 



Then, after noticing the absence of palatal teeth in the Crocodilia 

 and several genera of Lacertilia, Cuvier proceeds : — "Les iguanes, 

 les anolis, les lezards ordinaires, les marbres et un certain nombre 

 de scinques, parmi les sauriens, partagent seuls avec plusieurs 

 serpens, batraciens et poissons cette armure singuliere. Mais les 

 iguanes et autres sauriens la portent aux pterygoidiens seulement ; 

 les serpens, aux palatins comme aux pterygoidiens ; les grenouilles, 

 les rainettes, les salamandres, aux vomers, les premieres sur une 

 ligne transversale, les autres sur une ligne longitudinale. Plusieurs 

 poissons," &c* But it is unnecessary to follow further the great 

 palaeontologist's exhaustive analysis. Suffice it that he hits the fact 

 which distinguishes Mosasaurus from the Ophidia, and which unites 

 it with the Lacertilia. The advocate for the sea-serpentism of the 

 extinct Mosasauroids determines the pterygoids to be the palatines ; 

 and if so, the missing bones posterior to Prof. Cope's palatines might 

 also have borne teeth, and thus the ground taken by Cuvier, in 

 the sole comparison which he makes with serpents, would be cut 

 away. But, irrespective of the obvious concordance of the bones 

 figured by Prof. Cope as palatines with the unquestionable pterygoids 

 of the specimen cited, and before me as I write, it is much more 

 likely that the smaller, true, edentulous palatines should have 

 escaped observation and collection than the larger and more poste- 

 riorly situated pterygoids ; it is hardly conceivable that these should 

 be missing in every one of the numerous and well-preserved 

 specimens which the North- American Cretaceous series has afforded. 



* Tow. cit. p. 322. 



