248 TEETIAET VEETEBEATA OE THE FATtM. 



anterior root of pm. 3, and beneath it a smaller aperture. The alveolar border is 

 broad : in front are the large single alveoli for the canine, which is much larger than 

 the incisors, and for the first premolar, behind and to the outer side of which are 

 shallow pits for the points of the lower teeth. Then come the alveoli for the large 

 double-rooted pm. 2 ; behind and to the inner side of the posterior root of this and 

 the remaining premolars are deep fossae for the reception of the points of the lower 

 teeth. The third and fourth premolars are large three-rooted teeth which will be 

 described below. The first molar is beneath the orbit ; it had two or three roots, there 

 being doubt as to whether the wide posterior root is merely grooved or actually divided 

 into two. Whether any other molars were present is uncertain, but probably there was 

 at least one more. The palatine surface of the maxilla is raised into a broad ridge 

 as far back as the hinder end of the second premolar ; then it flattens out to form 

 the palate and unites behind with the palatines in an oblique suture : there is 

 a pair of small posterior palatine foramina. The inner face of the bone forming the 

 wall of the nasal passage is strongly concave from above downwards : on this face 

 towards the anterior end of the bone is a strong longitudinal ridge increasing in 

 height backwards, perhaps representing the maxillo-turbinal. The lachrymal (la.) 

 is a small element forming a slight projection at the anterior border of the orbit 

 and wedged in between the frontal, the . jugal, and the maxilla. The jugal [ju.) 

 is a comparatively stout bar of bone, the anterior end of which is thrust 

 between the lachrymal and the backward prolongation of the maxilla ; it forms 

 the ventral border of the orbit. Its free portion is slightly flattened from above 

 downwards in front and from side to side posteriorly ; its pointed posterior end 

 underlies the strong zygomatic process of the squamosal (sq.). This bone is very 

 large and forms the whole of the great lateral expansion of the hinder part of the 

 skull. Posteriorly it unites with the supraoccipital above, then with the exoccipital, 

 and below this again with the mastoid portion of the periotic. External to this 

 it forms a broad concave surface, looking backwards and forming the lateral region 

 of the posterior face of the skull. The lambdoidal crest is continued on the 

 squamosal, running downwards in an S-shaped curve, then becoming continuous with 

 the sharp upper border of the zygomatic process. The upper edge of the bone unites 

 with the supraoccipital and in front of this with the parietal, the line of union with 

 which runs downwards and forwards and is raised into a moderately prominent ridge. 

 Its anterior border is produced forwards as a sharp-edged shelf, the lower face of 

 which is occupied by the glenoid articulation for the mandible. The large zygomatic 

 prominence (zyg.) projects considerably beyond the rest of the bone; posteriorly it 

 is produced downwards into a large flange-like postglenoid process. The anterior 

 free portion of the zygomatic process is convex externally, its upper edge being 

 continuous posteriorly with the lambdoidal crest, as already mentioned ; the jugal 

 runs back beneath it as far as the anterior boundary of the glenoid surface. 



