176 On the Campus 



board of Nature to prevent check-mate. The thickening 

 and hardening of the wall enclosing the embryo was 

 the first move ; the sweetening and coloring of the outer 

 cover of the fruit, the second. That is, granted that 

 the animal's service is an advantage, then it is evident 

 that that plant will receive more frequent service which 

 proves to its serving visitors more attractive. The sweet- 

 er the cherry up to the limits of the bird's appreciation 

 of sweet, and the more clearly contrasted against the 

 foliage of the tree, the greater the number of visitors, the 

 more wide the dispersal of the seeds. 



This gave us the wild cherry of all forests, and is the 

 limit of differentiation, as between bird and fruit. In 

 the old world the wild cherry is native of central Asia 

 and its small sweet fruit is black or wMte. Now comes 

 the agency of man. If the cherry has responded to 

 birds, much more promptly to human selection. Edible 

 cherries were found on the tables of the Greeks and Ro- 

 mans, and have not in all the centuries failed us until 

 now, when the thick-pulped black and white cherries of 

 California are carried around the world. Our sour, com- 

 mon red cherries are derived in similar fashion from 

 another very similar Asiatic stock; but, somewhat more 

 enduring of our valley climates, are more widely known, 

 and when the robin lights next amid the shining spheres, 

 reflect ; he is there but to take his own, to collect an 

 ancient royalty. Robins and birds were horticulturists 

 ere Adam delved or Eve span. 



The agency of man in this process which I have taken 

 as illustrative of all the fleshy stone-fruits is therefore 

 but supplementary, accelerative. The birds evolved the 



