194 ANIMAL LIFE AND WINTER. 



of success, the hare and ptarmigan are more likely to 

 escape observation than they possibly could in their 

 summer dress when snow is on the ground. 



But we must remember that this also is a hereditary 

 quality which appears at a particular time, and sometimes 

 is present when snow is absent. The ptarmigan, for 

 example, may sometimes be seen in late autumn as con- 

 spicuously white objects upon their native hills, which as 

 yet are bare of snow. 



" The ptarmigan that whitens ere his hour 

 Woos his own end." (Tennyson.) 



But although this adaptation may thus fail in some years, 

 there is no doubt whatever but that for the saving of the 

 race at large it also is effective. 



(5) To a great many creatures, particularly invertebrate 

 types, winter brings death to the individual, but the race 

 survives in the eggs, which pass the winter in a dormant 

 state. Such are rotifers, fresh-water sponges, various 

 insects. Many insects are creatures only of a year or less. 



(6) Lastly, there are a great many who face the winter 

 and make the best of it. Some of them do not survive, for 

 winter is a great eliminator. Others live through it an 

 illustration of the survival of the fit. Our resident birds 

 are the best example of this group. 



