34 THE NATURAL HISTORY 



LETTER XV. 



TO THE SAME. 



Selborne, March 30, 1768. 

 DEAR SIR, 



SOME intelligent country people have a notion that we have, in 

 these parts, a species of the genus mustelinum, besides the weasel, 

 stoat, ferret, and polecat ; a little reddish beast, not much 

 bigger than a field mouse, but much longer, which they call a 

 cane. 1 This piece of intelligence can be little depended on ; but 

 farther inquiry may be made. 



A gentleman in this neighbourhood had two milkwhite rooks 

 in one nest. A booby of a carter, finding them before they were 

 able to fly, threw them down and destroyed them, to the regret 

 of the owner, who would have been glad to have preserved such 

 a curiosity in his rookery. I saw the birds myself nailed against 

 the end of a barn, and was surprised to find that their bills, 

 legs, feet, and claws were milkwhite. 



A shepherd saw, as he thought, some white larks on a down 

 above my house this winter : were not these the emberiza nivalis, 

 the snow-flake of the Brit. Zool. ? No doubt they were. 



A few years ago I saw a cock bullfinch in a cage, which had 

 been caught in the fields after it was come to it's full colours. 

 In about a year it began to look dingy ; and, blackening every 

 succeeding year, it became coal-black at the end of four. It's 

 chief food was hempseed. Such influence has food on the colour 

 of animals ! The pied and mottled colours of domesticated 

 animals are supposed to be owing to high, various, and unusual 

 food.2 



1 had remarked, for years, that the root of the cuckoo-pint 

 (arum) was frequently scratched out of the dry banks of hedges, 

 and eaten in severe snowy weather. After observing, with some 

 exactness, myself, and getting others to do the same, we found 



1 [This is probably nothing but a female weasel, the female in this species being 

 decidedly smaller than the male.] 



2 [Many like cases of change of colour induced by change of food are now re- 

 corded. Larks have been observed to turn black when fed on hemp seed ; canaries 

 to redden on cayenne pepper ; green parrots to develop red and yellow feathers 

 when fed on fish or pounded maize. A shipwrecked crew subsisted for a long 

 time on penguins' eggs, and it was remarked that their hair and complexion 

 turned lighter, black tiair becoming brown or red. See Distant on "Assimilative 

 Coloration," Zoologist, 4th ser., vol. ii., p. 400 (1898).] 



