334 ANATOMY OF VERTEBRATES. 



manifest the most tuberculate and omnivorous character of the 

 teeth. The formula is — 



.3.3 1.1 3.3 1.1 



The canines are strongly developed, well pointed, with a poste- 

 rior trenchant edge ; they are more compressed in Arctonyx than 

 in Meles. The first lower premolar is very small, single-fanged, 

 and, generally, soon lost. The first above, corresponding with 

 the second in the Dog, is also small, and implanted by two con- 

 nate fangs. The second upper premolar, p 3, has a larger, but 

 simple, sub- compressed conical crown, and is implanted by two 

 fangs. The third repeats the form of the second on a larger scale, 

 with a better developed posterior talon, and with the addition of 

 a trituberculate low flat lobe, which is supported by a third fang ; 

 the outer pointed and more produced part of this tooth represents 

 the blade of the sectorial tooth and the entire crown of the 

 antecedent premolars. The true molar in Meles is of enormous 

 size compared with that of any of the preceding Carnivora ; it 

 has three external tubercles, and an extensive horizontal surface 

 traversed longitudinally by a low ridge, and bounded by an 

 internal belt, or ( cingulum.' 



In other allied genera, which, like the badgers, have been 

 grouped, on account of the plantigrade structure of their feet, 

 with the bears, a progressive approximation is made to the type 

 of the dentition of the Ursine species. The first true molar 

 below soon loses all its sectorial modification, and acquires its 

 true tubercular character ; and the last premolar above becomes 

 more directly and completely opposed to its homotype in the 

 lower jaw. The Racoon (Procyon), and the Coati (Nasua), 

 present good examples of these transitional modifications; they 

 have the complete number of premolar teeth, the dental formula 

 being — 



.3.3 1.1 4.4 2.2 

 t 3^ ;C Ll^474 ;?n 272 = 40 - 



That of the Benturong (Arctictis) and Kinkajou ( Cercoleptes) is — 



.3.3 1.1 3.3 2.2 



1 O 1 C l7l>P £*> m 2* = 36 * 



The lower canine of Nasua has a deep longitudinal groove on the 

 inner side of the crown. In Aihirus both upper and lower canines 

 present two longitudinal grooves. In Cercoleptes a longitudinal 

 ridge divides the two grooves on the canines. A fossil canine 

 tooth from the eocene sand at Kyson presents a still greater 

 number of grooves and ridges, whence the name Pricynodon. 

 The essential characteristic of the dentition of the Bears, fig. 



