JULY. in 



sparrow looks so like its mother in size and plumage 

 that you only discover its youth from its ineffectual 

 attempts to rise from the ground. Yet baby part- 

 ridges, scarcely bigger than sparrows themselves, 

 can make a very creditable imitation of the whirring 

 flight of a full-grown covey over considerable dis- 

 tances, rising and alighting almost simultaneously 

 with their parents. If you examine a partridge's 

 wing, you will notice that the curved quills are pecu- 

 liarly hard and stiff. To these qualities are due the 

 loud whirring of their flight, and also the fact that so 

 heavy a bird can rise quickly from the ground, and 

 to a certain extent the immature quills of the young 

 birds share these powers. 



NECESSITY THE MOTHER OF EVOLUTION. 



How have young partridges acquired the power of 

 flight ? There is a well-known story of the man who 

 described how his dog chased a beaver until it escaped 

 up a tree. " But," objected a listener, " beavers can't 

 climb." " This beaver," said the story-teller, " had to 

 climb, the dog crowded him so." Though untrue of 

 the individual beaver, the sentence might be para- 

 phrased as the correct explanation of the way in 

 which all kinds of creatures have acquired their various 

 special powers. Animals which swim, fly, or climb, 

 could not do so originally ; but, as evolution went on, 

 they had to, the others were crowding them so. So 

 young partridges, feeding in the open, where they 

 would be at the mercy of a swift animal foe, have to 

 fly at an age when other birds, living safely in nests 

 in trees and bushes, can do little more than gape for 



