DEPARTING SUMMER VISITORS 173 



existence all down the ages must lead to the survival 

 of types and forms best suited to their special 

 environments. Birds best adapted and equipped for 

 catching fish or for opening seed pods will get most 

 fish or most seeds, will grow strongest, and in the 

 inevitable struggle will drive off the less fit. But 

 whence the colours and markings that appear with 

 such wonderful regularity in various species i Each 

 feather in its place and order will show markings 

 that blend together into a pattern, and all will be 

 faithfully and minutely repeated in every specimen. 

 It is a problem as deep as that of the *' little flower of 

 the crannied wall/' The Tanager does not moult 

 his brilliant colours and bring forth a covering more 

 suited to the advancing season. His feathers have 

 changed their colour with the passing of the spirit 

 that found expression in the love song warbled from 

 the high limb of a dead but defiant pine. The same 

 feathers that glowed scarlet in the spring sunshine 

 reflect only a dull, insignificant, yellowish green. 



The most sociable and happy of our little transients 

 is the Wild Canary or Thistle Bird, sometimes called 

 the American Goldfinch. He seems quite as happy 

 and glad as in the season of brilliant plumage and 

 loud song. These little fellows are now hammering 

 the seeds out of the Wild Sunflower heads and 

 vigorously attacking the withered Asters. All seeds 

 are acceptable, for they even pry open the cones 



