SPOTS AND STRIPES IN MAMMALS 35 



again, may be regarded as a transversely striped marsupial, 

 although here the stripes are few in number and approxi- 

 mate in form to blotches. Although in the same order the 

 dasyures are spotted with white, we have no black-spotted 

 marsupial ; and if such a type formed the transition 

 between longitudinal and transverse stripes, surely some 

 species showing such a type of coloration ought to have 

 persisted. 



Then, again, in the ungulates we have the zebra- 

 antelopes, the gnus, and the zebras showing most strongly 

 marked transverse dark stripes ; but we have no dark- 

 spotted forms in the whole order except the giraffes, while 

 the only ones with dark longitudinal stripes are young 

 pigs. And it would thus appear that, although all the 

 animals above mentioned are highly specialised species, 

 these tranverse stripes and dark blotches must have 

 originated de novo quite independently in each of the 

 groups in question. Indeed, when we remember that the 

 coloration of zebras, antelopes, and giraffes is generally 

 of a protective nature — the stripes of the former rendering 

 the animals invisible on sandy ground in moonlight, and, 

 to a great extent, also in sunlight, while the blotches of 

 the latter harmonise exactly with the chequered shade 

 thrown by the mimosa-trees among which they feed — it 

 is incredible that both types should have been evolved, 

 according to a rigid rule, from animals marked by dark 

 longitudinal stripes. 



Another instance of the same nature is afforded by the 

 cats, in most of which the coloration appears to be 

 mainly of a protective nature, plain-coloured species, like 

 the puma and lion, having tawny coats harmonising with 

 the sandy deserts which these animals often inhabit, while 

 the vertical stripes of the tiger, although in some degree 



