INTRODUCTORY REMARKS. 81 



del Fuego,* it is likely that the latter have often a 

 fifth toe on the hind feet, as well as the former, 

 who are mostly provided with it. In these respects, 

 the races of South America assimilate with the old 

 terriers of Europe, as they do also in several other 

 particulars. 



Having already adverted to the skulls of canines 

 in general, we shall defer further notice until we 

 describe the structure of the primitive races. 



There is no typical colour of the hair assignable 

 to dogs ; though, perhaps, a kind of fulvous buff is 

 the most frequent, in all the regions of moderate 

 and fervid temperatures. And it may be observed, 

 that the author of the British Field Sports has justly 

 remarked, that all the great and ancient races of 

 dogs are originally divided into a rough and smooth 

 variety, which appear to be independent of climate ; 

 for both are found to continue under opposite cir- 

 cumstances. 



No domestic dog is provided with a tail that 

 reaches to the ground, or forms a real brush, like 

 that of foxes ; the organ is not so flexible as in the 

 last mentioned, but rigid, and mostly drawn up 

 into a curve, with the point towards the back. In 

 joy, it wags from side to side ; in fear, it is with- 

 drawn between the legs. The ears of dogs are 

 originally upright and pointed, in aU the -races 

 having long hair and a sharp muzzle; in those 

 where the head is similarly terminated, but the 

 bair is short, they are half erect; in the blunt- 

 * Communicated in a letter by Captain Fitzroy, R. N. 



