CONDYLARTHEA. 393 



above the middle of the last premolar. The foramen infraorbitale is above 

 the middle of the third superior premolar. The anterior part of the malar 

 bone is quite prominent, overhanging the maxillary, and bounding a shal- 

 low fossa which is open below. A crushed skull of the large variety 

 displays a strong sagittal crest, arising from gradually converging rather 

 obscure temporal ridges. Another skull has the parietal region much 

 depressed, which is not altogether due to pressui*e, as the sagittal crest is 

 partly intact. There is a strong supraoccipital crest, which is bilobed, the 

 convex lateral portions being separated by a deep median notch. Between 

 their bases the occipital face of the skull is concave. The paroccipital 

 process is separated from the occipital condyle by a strong notch. It does 

 not extend quite so far as the rounded, robust mastoid or posttympanic 

 process, to which it is closely attached. At its inner base there is a rather 

 large ? stylomastoid foramen. The postglenoid process is peculiar, being 

 an angular ridge terminating interiorly in a low angular tuberosity. Its 

 posterior side, or that of the base of the zygoma, is flat, and slopes for- 

 wards and downwards. The glenoid cavity is nearly flat, and has no pre- 

 glenoid crest, on the inner part at least; the rest of the border being 

 destroyed in my specimens. The surface is cut off within by the groove, 

 which, entering the roof of the meatus auditorius, I'epresents the foramen 

 ovale. On the internal side of this groove there is a ridge, which, at its 

 middle, swells into a tuberosity. The meatus auditorius is widely open. 

 The postglenoid and supragleuoid foramina are rather small, and the latter 

 is exactly above the postglenoid ridge. The mastoid foramen is on a line 

 with the suprameatal ridge. The superior part of the mastoid bone just 

 behind the posttemporal crest is pierced by another smaller foramen. 



The lengths of the last five inferior molars in this species vary from 

 M. .065 to .055 ; and the inferior true molars from .035 to .033. The fol- 

 lowing measurements are taken from two individuals : 



Measitrements. 



No. 1. 



H. 



Length of inferior dental series, less incisors 090 



Length of inferior premolar series 046 



Xength of inferior true molar series 034 



Leuartliof basePm. i .. .108 



