2^12 SCOTT. [Vol. XI. 



zone is somewhat shortened as compared with that of the 

 tragulines, and very much so when contrasted with the long 

 parietals of such genera as Oreodon or Ancodus. For most of 

 their length the parietals unite to form a thick and prominent 

 sagittal crest, which is cancellous internally and encloses a 

 small sinus. Anteriorly, near the frontal suture, the crest 

 bifurcates into two temporal ridges, which are recurved and 

 overhanging, thus enclosing a deep grove in which a goose- 

 quill may be concealed. These temporal ridges are confined 

 to the parietals, and become thickened and more rugose at the 

 points where in the male skull the large protuberances arise. 

 These thickened areas differ somewhat in shape and in promi- 

 nence in the various specimens, but in none of the skulls be- 

 fore me do they rise into protuberances at all comparable even 

 with those of the specimen figured by Marsh (No. 6, PL XXI, 

 Fig. i). In most of the female skulls the parietals extend 

 quite far down upon the sides of the cranium, though there is 

 variation in this respect, and in front of the squamosals send 

 down narrow processes to meet the alisphenoids. The latter 

 are antelopine rather than cervine in shape, which is no doubt 

 due to the great amount of backward displacement which the 

 orbit has undergone. The ascending process of the alisphe- 

 noid is narrow, but its lower portion is reflected backward, and 

 internally to the glenoid cavity extends almost to the tympanic. 

 The pterygoid process is also narrow and has decidedly less 

 vertical height than in recent Pecora. 



The basisphenoid forms a rather slender and almost cylin- 

 drical rod, which is distinctly narrower than in the deer. The 

 tympanic is much like that of MoscJms ; the exceedingly small 

 bulla is but seldom well preserved, so that it is not surprising 

 that Marsh should have concluded that " there were apparently 

 no auditory bullae" (No. 5, p. 82). The bulla is produced 

 anteriorly into a long, slender spine, and on its postero-exter- 

 nal side is a deep pit for the tympano-hyal. A long auditory 

 meatus occupies the space between the postglenoid and post- 

 tympanic processes of the squamosal, but does not form a com- 

 plete tube, the upper part being covered in by the squamosal. 

 Sir Victor Brooke's account of these structures in the musk deer 



