Dr. A. Giintlier on Chrysochloris Trevelyani. 347 



more so in perfectly adult animals than in younger ones, in 

 which this region is rather more convex. The occipital crest 

 is high, broad, presenting a rough surface behind ; each of its 

 halves is curved forward, and, detaching itself from the 

 cranium, it forms, together with the posterior part of the malar 

 bone, a broad, high, vertical shield, protecting the temporal 

 fossa in its entire depth. The remainder of the zygomatic 

 arch is not broader than in the much smaller C. capensis. 

 The suture between the squamosal and malar bones is per- 

 sistent, vertical, terminating below opposite to the glenoid 

 fossa ; and it is at this place that the greatest breadth of the 

 skull is situated. The orbits are, as generally in Chrysochloris, 

 incomplete ; and there is no trace of a postorbital process ; 

 neither is the skull constricted laterally behind the orbits. As 

 in C. capensis the premaxillary is produced on each side in a 

 short process, which, however, is not so much twisted or 

 flattened as in that species ; on the other hand, the nasal aper- 

 ture is more open, the nasal bones advancing less forwards, so 

 that the terminal portions of the simple naso-turbinal and the 

 more complex maxillo-turbinal can be clearly seen. A well- 

 developed sagittal crest extends from the occipital crest to the 

 nasal bone. The bony vesicle in the temporal fossa, which is 

 so prominent in the other Chrysochloris, is much less developed 

 and lower down in the fossa. The palate is of moderate width, 

 widest between the tme molars, rather concave antero-poste- 

 riorly. It is perforated by numerous minute foramina, but 

 otherwise perfectly ossified, with a prominent tubercle on each 

 side in front of, and close to, the posterior margin, which 

 itself is not thickened but provided with a pointed median 

 projection. This posterior margin is at some distance behind 

 the level of the last molar. The hamular processes of the 

 pteiygoids are very long, slender, and pointed ; the interptery- 

 goid fossa is deep, narrowing back^vards and ending in an 

 excavation. 



The auditory bulla is well developed, of a transverse oval 

 shape, at its lower convex surface traversed by a curved ridge, 

 the convexity of which is directed backwards. At its interno- 

 anterior base, behind the hamular process of the pterygoid, 

 there is a vacuity in the bulla, the orifice of the Eustachian 

 canal, Avhich is covered by a separate lunate ossicle (fig. B, a), 

 leaning against the lateral wing of the basisphenoid. This 

 singular ossicle, which does not exist in C. cajjensis, is but 

 loosely attached to the surrounding bones and easily detached 

 with the soft parts. 



There are no paroccipital or mastoid projections, or tlie 

 former is but slightly indicated. The glenoid cavity is small, 

 fiat, convex behind, transverse, bounded by the cranial wall 



