MACHAIRODUS. 97 



convex than in Felis, and just behind the post-orbital processes are more deeply 

 excavated and of much greater vertical extent. 



The sagittal crest, though broken in the specimen, can yet be seen to have been 

 prominently elevated and strong to the point of its bifurcation. 



The forehead is much more strongly arched than in Felis, and also is more 

 depressed along its median line. 



The coronal and squamous sutures are entirely co-ossified in the specimen, and 

 the frontal suture is also obliterated, but its original position is indicated by a 

 rugged line. • 



The face is relatively much broader superiorly than in Felis, and along the sides 

 of the ossa nasi it is rendered prominently convex by the greater degree of exten- 

 sion, upward and backward, of the canine alveoli than in the latter genus. 



The posterior portions of the ossa nasi, remaining in the specimen, are relatively 

 narrow compared to those of the Panther, are placed slightly below the general 

 level of the corresponding part of the forehead and face, and are quite flat and 

 slightly inclined towards each other. 



The intermaxillaries are not quite so prominent forward as in Felis, but they are 

 rather stronger, in accordance with the greater size of the incisive teeth. 



The inion, which at its upper part is broken, appears to have had nearly the 

 same form as in Felis; but the short thick paramastoids are situated higher, and 

 the fossaa between them and the occipital condyles are less deep. 



The latter and the occipital foramen have the same form and relative size and 

 position to each other as in Fells. The foramen is transversely oval, nine lines in 

 its greater, and six and a half lines in its shorter diameter. 



The base of the skull, for the most part, is enveloped in a hard matrix, which 

 to remove would endanger the integrity of the much fissured specimen; neverthe- 

 less it presents a few points visible and worthy of notice. 



The mastoid processes are a little more advanced in their position, and more 

 internally situated than in Felis. 



The anterior condyloid foramina are more exposed in their position than in Felis, 

 or rather they are not directed to the same extent into the exit of the jugular 

 canal. 



The auditory bullae, though broken away in the specimen from their remaining 

 connections, may be inferred to have been as well developed as in Felis. 



Inferior Maxilla. — (PI. XVIII. 1, 3.) The lower jaw corresponds in its general 

 form with that of the latter, but it presents the same remarkable characters as in 

 the other known species of Machairodus. 



The coronoid process is relatively very short compared with that of Felis, and, 

 instead of curving backward, its posterior border is quite vertical to the base of the 

 bone. 



The extent of the fossa below the coronoid process, and the form of the condyle, 

 are about the same as in Felis. 



The post-coronoid process is short and thick, and is bent outward instead of 

 inward, as in Felis. 



The external surface of the lower jaw, near the base and below the position of 



