SKELETON OF ARTIODACTYLA. 



467 



olfactory surface ; the orbital surface being the largest, and the 

 superorbital ridge broad and much produced. The petrosal, mastoid. 



313 



314 



Skull of Young Pig (Sus). 



tympanic and squamosal elements of the temporal have coalesced. 

 The meatus internus is a deep fossa divided into a cribriform 

 surface below and a canal above : the 

 tympanic swells into a large three- 

 sided conical protuberance below. The 

 palatines prolong the bony palate be- 

 yond the series of grinding teeth in 

 use. 



The composition of the Mammalian 

 skull has been more fully exemplified in 

 the young of the genus Sus (p. 300, 

 fig. 189). In fig. 314, is given a back 

 view of the neural arch of the occipital 

 vertebra, showing the flattened cen- 

 trum (basioccipital), c 3, the neurapo- 

 physes (exoccipitals), c 2, with their 

 convex post-zygapophyses or ' con- 

 dyles,' and long descending diapophy- 

 ses (paroccipitals). The neural spine (superoccipital), c i, is a 



n H 2 



Occiput (Sus). 



