SPOTS AND STRIPES IN MAMMALS 29 



coat is an acquired or specialised feature. And the same 

 holds good for other groups. 



Turning to the carnivorous mammals, we find that in 

 many families, more especially the cats, hyaenas, and civets, 

 stripes and spots are far more generally present than 

 a uniform coloration ; although some groups, such as the 

 bears, form a marked exception to this rule, the majority of 

 the species being uniformly coloured, while none are striped 

 or spotted. In some species of the weasel family notably 

 the badgers it may be also noticed that while the sides 

 of the head are marked by longitudinal dark and light 

 stripes, the remainder of the body is uniformly coloured. 

 And it may be mentioned here that many animals, such as 

 donkeys and dun-coloured horses, retain a longitudinal dark 

 stripe down the back, frequently accompanied by dark trans- 

 verse bars on the limbs, while a uniform coloration prevails 

 elsewhere. 



In the gnawing mammals, or rodents, although many 

 species are uniformly coloured, stripes and spots are pre- 

 valent ; and a survey of the collection of these animals in a 

 good museum will show that, whether the pattern take the 

 form of stripes or of spots, the arrangement is invariably 

 longitudinal and never transverse. Indeed, it may be 

 observed that when spots are present, these are invariably 

 light-coloured on a darker ground. Although in many 

 cases the longitudinal stripes occupy the whole or a con- 

 siderable portion of the upper surface, in some of the 

 squirrels they are reduced to a dark and light stripe, or 

 even a single light stripe on each flank, this remarkable 

 type of coloration recalling the "speculum" on the wing 

 of a duck. 



I might extend this survey to other orders of mammals, 

 but sufficient has been said to indicate the variability of 



