HYAENA SPEL^EA. 139 



The four lower molars all belong to the spurious series, 

 the last being the sectorial tooth. The upper jaw of the 

 Hysena has five molars on each side, a small tubercular 

 true molar terminating the series, which includes four, in- 

 stead of three premolars as in the genus Fells. 



The most characteristic modification in the dentition of 

 the Hysena is the strong conical shape of the second and 

 third premolars, in both upper and lower jaws, the base of 

 the cone being belted by a strong ridge, which defends 

 the subjacent gum.* This form of tooth is especially 

 adapted for gnawing and breaking bones, and the whole 

 cranium is modified by the enormous developement of the 

 muscles which work the jaws and teeth in this operation. 

 The tooth of the Hysena most liable to be mistaken for 

 one of a large Feline animal, is the sectorial or last molar 



Fig. 55. 



Nat. size, Kirkdale Cavern. 



of the lower jaw (fig. 55) ; it is distinguished by the 

 presence of two small tubercles, one at each end of the base 

 of the crown. 



* An eminent civil engineer, to whom I once showed the jaw of a Hysena, 

 said, that, if he wanted a model for the form of a hammer best adapted for break- 

 ing stones for roads, he should take the strong, conical, ridged tooth of that 

 animal. 



