DOG TRIBE. 



493 



\ premolars, and | molars. If this formula be compared 



the number of 



^ mcisors, } canines, 



with the one given on p. 449, it will be seen that the excess in 

 the teeth of a dog over those of a civet is owing to the presence of an additional 

 pair of molars in the lower jaw. This will not, however, serve to distinguish 

 between all the dogs and the civets, since the Indian wild dogs have but two pairs 

 of lower molars. In all cases there are four premolar teeth on each side of both 

 jaws. The cheek-teeth of the dogs are constmcted on the same general plan as 

 those of the civets, the upper flesh-tooth having but two lobes to the blade, while 

 the lower flesh-tooth has a large heel posteriorly to the cutting-blade ; this heel 

 being, however, relatively smaller than in the civets. In both dogs and civets, the 

 molars of the upper jaw have the same general triangular form. A good idea of 

 the characters of the 

 cheek-teeth of the dogs 

 will Ije gathered from the 

 accompanying figure, 

 while the skull repre- 

 sented on p. 3.52 shows 

 the lateral aspect of the 

 whole dental series. 



There are other char- 

 acters connected with the 

 skull, together with many 

 points in the stnicture of 

 the soft parts, which afford 

 additional means of dis- 

 tinguishing the dogs from 

 other Carnivores, but the 

 above are sufiicient to 

 define the group, so far 

 as living forms are con- 

 cerned. 



In their general uni- 

 formity of structure and 

 outward appearance, the 



dogs differ widely from the civets, and more nearly resemble the cats 

 considerable amount of difference in external appearance between a fox and a 

 wolf, but intermediate forms connect them so closely that they are generally 

 considered as members of a single genus. On the other hand, three membere of 

 the family differ so remarkably from all the rest, and also from one another, that 

 they are regarded as the representatives of as many genera. Some diversity 

 of opinion exists as to the advisability of also referring the Asiatic wild dogs to a 

 distinct genus, but they are here classed in the tj^pical genus Canis. We thus 

 have the whole of the existing members of the family ranged under four genera, 

 of which the last three are severally represented by a single species. 



With the marked exception of the Cape hunting-dog, all the members of the 

 family are characterised by their more or less uniform and sombre coloration 



THE BIGHT UPPER AND LOWER CHEEK-TEETH OF THE COMMON FOX (a, a') 

 AND OF AZARa's fox (B, B'). 



The letters ;j.»n.l Xop.mA indicate the premolar, and in.\ to )n.3 the molar 

 teeth ; f.mA in the upper and in.\ in the lower jaw, being the flesh-tooth. 

 In JH.l of the lower jaw J indicates the hinder lohe of the cutting-blade, and 

 a its inner cusp. (From Proc. Zool. Soc— After Huxley.) 



There is a 



m 



