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less degree ; the outer surface is more convex than that of the coronoid process, 

 and is traversed by three nearly parallel longitudinal ridges, and by a fourth 

 shorter ridge which curves upwards. These indicate the strong insertion of 

 that part of the masseter which arises from the descending process of the 

 zygoma, and which protracts the jaw. The inner side of the angular process 

 presents a general and moderately deep concavity, bounded below by the inflected 

 inferior border of the process, and in front by a ridge extending from that border 

 obliquely upwards and forwards to near the alveolus of the last molar. Above 

 the termination of this ridge, and behind the last alveolus, a short vertical ridge 

 of bone projects inwards and backwards, and bounds anteriorly the concavity on 

 the inner side of the ascending ramus. The surface of this concavity is smooth 

 except at its posterior part near the concave border of the angular process, where 

 it is broken by some irregular ridges and impressions. 



The anterior part of the base of the coronoid process is continued by a convex, 

 smooth, osseous prominence or buttress, along the outside of the alveolar pro- 

 cess, for about two inches, gradually subsiding to the level of the outer plane of 

 the horizontal ramus. The alveolar tract of each ramus includes four sockets, 

 the two posterior of which are slightly inclined inwards ; the right and left series 

 of sockets diverge as they advance forwards : the sockets correspond of course 

 with the shape and size of the teeth, and are consequently of great depth. The 

 last two molars in the present specimen are worn down to the level of the alveoh, 

 the others project more as they advance forwards. The margin of the alveolar 

 outlet is rough ; in the last one it is rather broad, shghtly excavated, and rises 

 at a httle distance from the tooth as an irregular ridge, indicating that the molar 

 was surrounded by a thick and probably callous gum. The interval between 

 the first and second sockets is three hues, or nearly twice that of the interval 

 between the second and third, or the third and last sockets. A convex rising of 

 bone bounds the outside of the alveolar series, but is interrupted between the 

 first and second sockets. These, though they be slight indications of the di- 

 stinctive character of the first socket, are interesting, since the anterior molar of 

 the upper jaw, by its greater separation from the four posterior ones, more 

 decidedly represents a canine tooth ; and if the last large molar of the lower jaw 

 be regarded, from its peculiar form, as equivalent to the two separate posterior 

 molars in the upper jaw, then the first molar would correspond with the canine- 



