654 



THE CARNIVORES 



of its habitat the stoat invariably assumes the well-known white winter dress which 

 constitutes the valuable ermine of commerce. In the British Islands this change 

 always takes place in the Highlands of Scotland; while in the northern English 

 counties, like Northumberland and Durham, it is frequent but by no means universal. 

 Proceeding further south, the change of color becomes more and more rare, taking 

 place only occasionally in counties like Cambridgeshire and Lincolnshire, while in 

 Cornwall and Hampshire it is almost unknown. In North America the change 

 takes place in the more northerly parts of the United States and all the regions 

 to the northward; specimens captured during the winter in Massachusetts, New 

 York, and Pennsylvania being almost invariably white. Some of those from Vir- 

 ginia turn partially white, while in South Carolina there is no change at all. 



THE; STOAT OR ERMINE IN WINTER DRESS. 

 (One-third natural size.) 



The nature of the change from the dark summer to the white winter 

 dress in the stoat and other animals has given rise to much discussion. 

 It was originally considered that the animal sheds its coat in the autumn and 

 spring ; the dark summer coat being gradually replaced by the advent of the white 

 hairs of the winter one. Doubts then arose whether the change in color was always 

 coincident with the development of the winter and summer coat, and whether the 

 hairs themselves might not actually change color. Dr. Elliott Coues succeeded, 

 however, in proving that the change might take place in either way, some speci- 

 mens taken in spring showing the long, woolly, white, winter coat on some parts of 

 the body, while on other parts they had the short, coarse, brown hair of summer; 

 and he observes that ' ' we may safely conclude that if the requisite temperature be 



