SPOTS AND STRIPES IN MAMMALS 29 
coat is an acquired or specialised feature. And the same — 
an 
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 
