CHAPTEE XV. 



Carnivoees, — continued. 



The Dog Tribe. 



Family Caxid^E. 



Under the general title of Dogs may be inchided all the animals commonlj^ 

 known as wolves, jackals, foxes, and wild dogs, together with the various breeds of 

 domestic dogs. These collectively constitute the family Canidcv, and form a group 

 in some respects intermediate between the Carnivores treated in the two preceding 

 chapters, and those described in the three succeeding ones. The Dog family must 

 always have an especial interest, since it includes the animals which have become 

 more thoroughly the friends anil companions of man than any other creatures. The 

 origin of the domestic dogs is, however, shrouded in the mist of anti(|uity, and it 

 is still an open question whether the various breeds are descended from a single 

 wild stock, or whether they are the product of several species. 



The Dog family, as thus constituted, forms, at the present da}', a compact and 

 well-defined group, the wild members of which cannot be confused with those 

 of any other. The whole of them are characterised by their long and pointed 

 muzzles, their moderately long tails, and their perfectly digitigiade feet, furnished 

 with blunt, nearly straight, and non-retractile claws. Then, again, all the dogs 

 have but four toes on the hind -feet, while, with the exception of the African 

 hunting-dog, the number of toes on the fore-feet is five, of wliich the first, or 

 innermost, is shorter than either of the others, and does not touch the ground. 

 The limbs, although varying in relative length, are never so short in proportion to 

 the body as is the case in so many of the Civet familj^ The ears are pointed and 

 erect, but vary greatly in length in the different groups. Such are some of the 

 chief external characteristics of the dogs, but, in order to understand their distinc- 

 tion from other families of Carnivores, it is essential to pay attention to the skull 

 and teeth. In all dogs the skull, as shown in the figure on p. 352, is chai'acterised 

 bj' its elongated muzzle and the large number of teeth with which it is furnished ; 

 in both of which respects it is M'idelj' different from the skull of the cats. On the 

 under-surface of the hinder part of the skull the tympanic bulla is inflated and 

 bladder-like, although it is not divided into two chambers bj' a complete septum. 

 This part of the skull serves, therefore, to distinguish the dogs from the 

 Carnivores yet mentioned, with the exception of the hyasnas. From the hycenas, 

 as well as from the cats, the dogs are readily distinguished by the number 

 and structui'e of their teeth. With but few exceptions, the total number of 

 their teeth is 42, or two more than the true civets ; the series consisting of 



