URSIDiE. 



)03 



like it, rises above the gum before the antecedent premolar has come 

 into place. One may still trace in the single anterior tubercle, 

 and the second pointed cusp in the outer side of the crown, the 

 rudiment of the blade and last remnant of the sectorial character of 

 this tooth. This representative of the blade, moreover, still plays 

 upon the last premolar above, receiving upon its outer side the 

 inner surface of the principal pointed lobe of that tooth ; but the 

 extensively developed tubercular posterior lobe of m 1 below is 

 opposed to the similarly formed crown of the first molar above. 

 The second true molar {m. 2, fig. 5 & 6) has a narrow oblong sub- 

 quadrate tubercular crown; which, like that of the first true molar, 

 is supported by two fangs. The crown of the third lower molar 

 (m. 3, figs. 5 & 6) is contracted posteriorly, and supported by two 

 connate fangs, it is relatively smallest in the Sun-bears and largest 

 in the great Ursus spelosus. 



Thus, guided by the important character of development and 

 succession for the determination of the molar teeth, the permanent 

 dental formula of the genus Ursus, is : 



Incisors — ; canines—; premolars—; molars — : = 42.(1) 



It is essentially the same both in number and kind of teeth as in the 

 genus Canis, but the individual or specific varieties which, in the Dog, 



(1) The molar series of the Genus Ursus is classified by M. F. Cuvier as follows :— 

 fausses molaires — , carnassieres j^rjj tuberculeuses 5^2* — ^^• 

 and by M. de Blainville thus : — 



avant-molaires 3^1, principales j^-i, arriere-molaires 3:^3 : = 26. 

 In the first formula the carnassial or sectorial teeth are rightly indicated as those marked p. 4, 

 fig. 3, and m 1, fig. 6, in PI. 130; but M. F. Cuvier does not show that the sectorial character 

 is a subordinate modification of teeth essentially belonging to two distinct categories, and an erro- 

 neous idea is thereby conveyed of the number of both premolars and true molars. In M. de 

 Blaimnlle's formula the number of true molars is correctly given ; but the teeth specified as 

 ' principales' have less claim to be so distinguished than the carnassials of Cuvier ; and, owing 

 to the absence of any natural character, different teeth are indicated as ' principales', in different 

 animals, in the ' Osteographie.' Thus, in the genus Felis the * principales' are the teeth marked 

 p. 3 in fig. 1, pi. 127. (See * Ost : des Felis, p. 55) ; and, in the genus Simla, they are the first 

 of the teeth marked m in fig. 1, pi. 117, Ost. des Primates, p. 43.; The principles of the clas- 

 sification and notation of the teeth of the molar series in the present Work will be explained 

 more fully after the description of the examples selected from the Order Carnivora. 



