6G ON THE EXTINCT MAMMALIA OF 



lobe. The fore part of the crown forms a nearly straight slope, extended at the base 

 in the feeblest degree compared with the condition in the cats. 



The sectorial molar is intermediate in the length of its crown in relation with its 

 breadth, compared with that of the cats and Di-epanodon primcevus. Its, shape is 

 intermediate to that of the cats and weasels. The crown is composed of a large 

 anterior conical cusp as in Putorius, and a posterior shorter trenchant lobe as in Felis. 

 Between the two lobes externally is a valley converging, as in the latter, though less 

 conspicuously, in a fossa or funnel-like pit. The principal cusp of the crown at its 

 inner part is extended as an abutment sustained by an internal fang, as in the cats 

 and weasels. 



The upper tubercular molar is a large tooth compared with that of the cats, though 

 less in its proportions than in the weasels. It has about the same proportionate size 

 as in Drepanodon primcevus, and also resembles it nearly in form. It is situated 

 behind the sectorial molar and extends transversely inward, as in the last mentioned 

 animal and in the weasels. It is invested by a pair of fangs, and has a tx'ansversely 

 clavate crown with the narrow portion internal. The outer half is double the depth 

 and thickness of the inner, and reaches to a level with the lower back part of the 

 sectorial molar. The inner half appears as if an angular segment had been removed 

 from it. The lower surface of the outer half slopes fore and aft from a median acute 

 ridge; that of the inner half is angularly concave transversely and convex from 

 before backward. 



The first lower premolar resembles the corresponding upper one. 

 The second and third lower premolars are like the corresponding teeth of cats, but 

 are devoid of the basal exjDansion at the back part of the crown. This is comjsosed 

 of a median pointed cusp proportionately longer and sharper than in cats, with a 

 small sub-lobe in front and Ijehind, the former being the smaller. 



The lower sectorial molar resembles that of Drepanodon jyrimcevus, and is interme- 

 diate in form to that of the cats and weasels. The crown consists of two broad 

 trenchant lobes as in the former animals, l^ut proportionately longer and less robust. 

 Back of the principal lobes is a sub-lobe, less well-developed than that of the 

 weasels. In one specimen it is double, as in the corresponding tooth of Drepanodoii 

 2yrimcevtis ; in the other skull the duplication is less marked. The internal valley of 

 the principal lobes converges into a funnel-like fossa more conspicuously than in the 

 same position in the last named animal, l)ut less so than in cats. 



The lower tubercular molar, the smallest tooth of the series, is like that of the 

 weasels in its form. It has an oval crown inserted l)v a sino-le fang. 



The comparative measurements of the two specimens of skulls and teeth of 

 Dinictis felina are as follows ; premising that many of them are not exact, but 

 approximative only, on account of imperfection in points of reference. 



