1903 Animal Colouring in Winter 15 



the herd should keep together, and thus avoid any " prying 

 pard," or, more accurately, any ravenous and marauding 

 Polar Bear, who might be on the look-out for a strayed in- 

 dividual, but who would not be capable of confronting the 

 whole herd of horned beasts. Thus recognition is more 

 essential than concealment from foes. The Raven again, 

 strong on the wing and in the bill, is capable of holding his 

 own against such small carnivora as the Ermine, who might 

 attempt to seize him when upon the ground. The Glutton, 

 too, is mainly a carrion-feeder, and thus needs no duplicity 

 of colour to aid in the cautious advance upon suspicious 

 herbivores ; nor does it fear as enemies any of the larger 

 carnivorous beasts which live in the tracts of country which 

 it inhabits. 



But, after all, it is highly difficult to formulate any positive 

 statements as to such advantages. Does the White Ptar- 

 migan really elude the Arctic Fox ? Is it not probable that 

 the latter has a keen scent, and would not be deluded by the 

 most perfect resemblance to a snowy environment ? As for 

 the Polar Bear, it has been pointed out again and again that 

 its white hue is far purer in the young Bear than in the 

 adult, and that old Bears have received the nickname of 

 "Old Brownie" by reason of their distinctly brownish tint, 

 which increases with age. Then, too, the perfectly just 

 criticism has been put forward, that at the first the change 

 to white in the winter, or to a complete white coat in the 

 case of such animals as the Snowy Owl and the Polar Bear, 

 which are white or nearly so all the year round, must have 

 been abrupt and final to be of any use. Probabilities at least 

 are against this ; and we have a case in point in the Virginian 

 Eagle Owl, which gets whiter as we approach the north. 

 Piebaldness would be more fatal on a protective theory than, 

 or certainly as fatal as, a marked and dark colouration. 

 There seems to be no way out of the assumption that we are 

 not to use that " universal key," natural selection, to explain 

 arctic lack of colouration. The fact that the direct stimulus 

 of the cold is requisite to produce the change is significant. 

 Had the habit, if we so term it, been engrained into the 

 nature of the beast by countless generations of rigidly 

 selected individuals, the change would at least for a time 



