208 FOSSIL REPTILES. 



tory nerves, a vertical lamina, which, were it ossified, 

 would probably appertain to the anterior sphenoid, as it does 

 appertain to it in such of the raminants as it exists in, that 

 is, in the Moschi. In the Saimiri, its lower front part is of 

 the ethmoid, and its hinder part of the anterior sphenoid. 

 All the upper part is membranous. The nature, then, of these 

 anterior frontal bones is clearly established, though their exist- 

 ence has been questioned by some comparative anatomists. 

 It is no business of ours to meddle with the controversy in an 

 humble compilation like this. It is sufficient for the satisfac- 

 tion of our readers to know that we follow the best of all 

 authorities. 



Behind the orbit is again another separated bone, which 

 completes the frame, by proceeding to join, by an apophysis, a 

 corresponding apophysis of the jugal. Inspection alone will 

 prove that this piece answers to that part of the frontal which 

 gives the postorbital apophysis ; and even the connexion of this 

 part with the jugal, in the ruminantia, is entirely similar to 

 that which takes place in the crocodile. This is named by the 

 Baron the posterior frontal. 



In fact, this piece is virtually nothing but the postorbital 

 apophysis. It performs the same functions, for it closes the 

 orbit, and is placed before the fossa temporalis and the crota- 

 phite. It has the same position and connexions, being situated 

 over the junction of the frontal and parietal bones. 



Behind the chief frontal and the two anterior frontals is a 

 large unequal bone, which covers all the middle and hinder 

 part of the cranium, and affords, by its sides, an attachment to 

 a part of the crotaphite. This presents no difficulty : it is the 

 parietal. It is simple in the crocodile, as it is in a vast num- 

 ber of quadrupeds when adult ; but it is double in a great num- 

 ber of other ovipara. It is even probable that it may be so 

 likewise in the foetus of crocodiles in no great degree of ad- 

 vancement, but it is simple in them on their coming out of 

 the egg. 



