NATURE'S CALENDAR 



or "varying" hare which is so called be- 

 cause it turns white in winter. This is 

 the case with many creatures of the re- 

 gions where the snowfall is deep and last- 

 ing. The ptarmigans are plentifully brown 

 in summer, but in winter altogether wiiite 

 in plumage, except certain tail feathers. 

 The same is true of the snow bunting and 

 of the great snowy owl, one of the fiercest 

 predatory birds of the Canadian zone. 



Certain mammals have the same ex- 

 perience. The arctic bear and arctic fox 

 are always white, for they inhabit the 

 regions of endless snow; but the big 

 Northern hare dwells in summer as far 

 south as our northern boundary, and in 

 summer is reddish-brown. Weasels are 

 familiar to us in their red-brown summer 

 coats, with white only inside the legs and 

 on the belly; but in winter this brown is 

 replaced by white, and the weasel, or stoat, 

 becomes the " ermine," so valuable as a 

 fur. 



Now this change is a preparation for 

 winter life in two ways, and it is accom- 

 plished, in the case of the weasel at least, 

 by a quick whitehing of the hair itself, 

 immediately following the first fall of 

 snow ; the same kind of weasels that live 

 south of snowy regions do not change at 

 all, and those which live, say about New 

 York, where in some winters no snow of 

 any account falls until late in the season, 

 delay their change until it comes and 

 then become white in a few hours. 



December 12 



December 13 



