958 MR. R. I. POOOCK ON WARNING COLORATION [DeC. 15, 



in warnino- coloration and his belief that the patterns of nauseous 

 species, to the conspicuousuess of which in their natural sur- 

 roundings several observers have testified, are procryptic. Prof. 

 Poulton has briefly replied to this view so far as butterflies are 

 concerned *. I will here endeavoui- to do the same as regards 

 the Mammalia. 



As stated in a demonstration given at the Gardens and sub- 

 sequently in conversation with me, Mr. Thayer holds that the 

 white markings of the Skunk, Badger, Ratel, Teledu, and Grison 

 ■serve to conceal these animals from the ground-prey upon which 

 they feed. The head of a Badger or Ratel, for instance, would 

 lose its shape when looked at from below, because the white 

 tracts would be cut out against the sky ; and this obliteration of 

 identity would be beneficial to the carnivore by enabling him to 

 capture field-mice and other ground-living species. Justification 

 for this hypothesis is found in the demonstrable fact that white 

 .spots and patches appear as sky-holes, especially in foliage, when 

 viewed from a lower level ; and it may be granted that the mark- 

 ings on the mustelines mentioned above may have the significance 

 claimed for them by Mr. Thayer when they are visible from 

 beneath. But I cannot bring myself to believe that his expla- 

 nation supplies the key to the guiding factor in their evolution. 

 Take, for example, the Teledu, the food of which is said to consist 

 of insects, larvae, and worms. It cannot be seriously claimed 

 that the Teledu is helped in getting food of this nature by the 

 whiteness of the top of the head and neck, because worms are 

 blind, whilst nocturnal ground-insects at best have feeble powers 

 of vision. Even if the Teledu feeds also upon mice and other 

 A'ertebrates with vision something like our own, which must be 

 admitted as a possibility, it is not very obvious how the narrow 

 median white spinal stiipe can be of any procryptic use in the 

 way claimed. It would for the most part be invisible to the little 

 animals. It would on the contraiy be in full view to an enemy 

 of larger dimensions than the Teledu, especially to one lurking in 

 a tree and looking down upon the musteline passing beneath. 

 So, too, with the Badger. This animal, as has been stated, lives 

 for the most part upon vegetable food, and it is difiicult to believe 

 that the catching of mice can have had a survival value in the 

 history of any individuals of sufiicient importance to the species 

 to guide the evolution of its facial coloration. On the other 

 hand, it is a demonstrable fact that Badgers gi-ubbing or trotting 

 -slowly about in the dusk, as is their wont, are quite conspicuous 

 to human eyes at a distance that could be covered by a wolf's or 

 lynx's spring, simply in virtue of the black and white bandings 

 on the head. It is quite easy to believe, however, that this same 

 |)attern must be procryptic against a suitable background of 

 white rocks with black interstices or of foliage with light shafts 

 breaking through, especially if the animal be still ; and it is quite 



* ' Essays in Evolution,' 1908, p. 321. ' 



