MAMMALS WITH CONTRASTED COLOURS 147 



We can understand that an animal something like a Pangolin, 

 when it got rid of its armour, and when hair was substituted for it, 

 as indeed we see has occurred in the little Pichiciago the hair 

 covering remained under the same nervous influences which by 

 habit its ancestors possessed when they had back-armour ; and in 

 all probability the contrast of coloration of the hair of some of 

 the descendants is caused by the same nervous influence. 



As a matter of fact we find that another animal, which we 

 might say is a brother of the Skunk we have been discussing, has 

 not this conspicuous warning coloration, although it possesses a 

 similar ' nauseous artillery.' This Common Skunk (so different from 

 the White-backed Skunk) has a black or blackish body, and ' although 

 there is a great amount of individual variation, the white markings 

 usually take the form of a streak' on the forehead, a spot on the 

 neck, and two stripes running down the back. ... In some cases 

 the white stripes do not extend beyond the neck, so that the back 

 is entirely black.' 



In the Common Skunk, it would seem, the change of colour has 

 gone on to such an extent as to leave nothing but mere vestiges of 

 its ancestral carapace-like white back ; and therefore the theory 

 of warning colours having been caused by ' mephitic ' influences 

 evaporates. 



It can be readily understood that possible enemies who may 

 come within the sphere of its effluvium don't require to see any 

 warning colours, they can smell the animal from a long distance, 

 and would naturally leave a good space between him and them ; 

 so that the ' mephitic ' warning may continue without the so-called 

 warning colours. 



One can hardly contemplate the Black-backed Jackal of South 

 Africa in the Zoological Gardens and not think its sharply defined 

 back related to an ancestral carapace. The Dingo of Australia has 



