504 CARNIVORES. 



affect the true molar teeth, are confined, in the Bears, to the pre- 

 molars. It would seem that in the genus Ursus the predominating 

 size of the large tubercular true molars had tended to blight the 

 development of the premolars. 



Rarely are these teeth all manifested in the adult animal, save in 

 some of the small frugivorous tropical Sun-bears. The second pre- 

 molar is the first to fall in both jaws ; the third next disappears ; and 

 the first and fourth only are most commonly found, separated by 

 an interspace in which some traces of sockets are occasionally percep- 

 tible, as in the Grisly, the Polar, the Black and the Brown Bears. In 

 the great extinct Bear of the Caves all the three anterior small premo- 

 lars were early lost ; and this appears to have been the case also with 

 an equally large and formidable extinct species, whose remains have 

 been discovered by Capt. Cautley and Dr. Falconer in the tertiary 

 formations of the Sub-Himalayan Mountain range. In the last pre- 

 molar of the upper jaw of this species (PI, 131, fig. 1 & 2, ^. 4) the 

 anterior talon is more developed than in the typical Ursidae ; the in- 

 ternal tubercle is continued from the posterior half of the base of the 

 crown. The first upper true molar (m. 1) has a quadri-tuberculate 

 crown, but the two inner lobes are smaller than the two outer ones, 

 and the transverse exceeds the antero-posterior diameter of the crown. 

 The second upper true molar (m. 2) has a square crown, as broad as it 

 is long, quadri-tuberculate, and thus resembling the form of that tooth 

 in some of the small Sub-ursine plantigrade quadrupeds. Of the den- 

 tition of the lower jaw of the Sewalik Bear I know only the three 

 true molar teeth ; and the socket of the last premolar {p. 4, fig. 3 & 4), 

 which was implanted by two fangs. The first true molar, (m. 1, fig. 

 3 & 4) which is the representative of the lower sectorial of the more 

 carnivorous FercB, has a simple compressed crown, with a middle 

 conical lobe and a basal talon before and behind, but no internal 

 tubercle. The second true molar (m. 2, fig. 3 & 4) has also a remark- 

 ably compressed crown, divided into two principal conical lobes ; the 

 posterior being the broadest. The last true molar repeats the com- 

 pressed character, but is broader anteriorly ; it has one principal 

 conical obtuse lobe, with a basal talon before and behind. Each of 

 the lower true molars is supported, as in the true Ursi, by two fangs. 



