472 DESCRIPTION OF A FRAGMENT OF 



tact, and appear to be united by suture ; posteriorly on each 

 there is a smooth, shallow cavity, represented in PI. XVI. Fig. 

 3, (I. d. Near the posterior extremity there is an appearance 

 of suture, which is most distinct on the left side, and which 

 in all probability marks the union of the dental with the 

 coronoid bone. The angular bones cannot be verv distinct- 

 ly made out; there is, however, on the left side near the 

 base, and along the whole extent of the specimen, an indi- 

 cation of suture, which I have no doubt is the union of the 

 angular and dental bones. 



The dental bone contains a single row of distinct alveoli, 

 continued in front, for the teeth ; just below the alveolar 

 border there is a series of foramina, one foramen to each 

 alveolus, for the transmission of the inferior maxillary nerve 

 and the blood vessels to the teeth. The teeth of the lower 

 jaw (and in the present specimen part of the dental bone, 

 owing perhaps to its being crushed) close within the upper. 



Just within the dental bone, on the left side, there pro- 

 jects a rectangular portion of bone, Fig. 2, and 4, s. be- 

 longing to the upper jaw : its character and analogies are 

 not very evident ; it is deficient on the right side. 



The intermaxillary bones are very distinct, and are seen 

 in Fig. 1, 2, and 4, b. ; they are united posteriorly by 

 squamous suture to the upper maxillary, and a bone which 

 appears to be the lachrymal. Anteriorly the intermaxilla- 

 ries are rounded, and separated about one-tenth of an inch ; 

 the anterior inferior portion of each is mutilated, but the 

 alveoli for the teeth are conspicuous, and from their direc- 

 tion we are led to infer that the upper front teeth project 

 beyond the lower; the posterior inferior portions of this 

 bone, each side, contain four or five teeth. 



Between the intermaxillary and upper maxillary bones 

 on each side, and covered principally by the former, is a 

 bone, Figs. 1, and 2, g, (the lachrymal probably,) in the an- 

 terior portion of which is a deep groove, Fig. 2, f, passing 

 forwards and downwards, and becoming smaller as it de- 

 scends; on the upper portion of each of these bones there 



