208 MAMMALIAN DENTITION 



which possesses broader crowns than the mandibular. The 

 three premolars increase in complexity from before backward 

 but not even the last becomes truly molariform :* each of the 

 upper premolars resembles half a molar. The cheek teeth are 

 plainly selenodont but the valleys between the cusps are only 

 partially filled with cement. The teeth cannot be called truly 

 hypsodont and indeed the first molar at least in all Cervidae is 

 obviously brachyodont. The upper molars shoAV the typical 

 ruminant obliquity of setting. A small globular style occurs 

 in the transverse furrow on the inner side of the first upper 



Fig. 75. — Lateral view of skull of Musk Deer (Moschus moschiferus, 9.7351-15). Note 

 the elongated upper canines and the short crowned cheek teeth. 



molar and the outer side of each lower molar. An extra cusp 

 is present upon the talonid of the last lower molar, producing 

 elongation of this crown as already noted above. Mastication 

 takes place on one side only at a time, a feature common to all 

 the Ruminants. 



Before passing to the Cavicornia it is worth while glancing 

 for a moment at the skull of the Musk Deer (Fig. 75), an ani- 

 mal more primitive in many respects than the true Deer and one 



*In the specimen figured the premolars have not yet erupted; their place is oc- 

 cupied by the deciduous molars. 



