Chap. I.J SELECTION BY MAN. 37 



natural capacity and years of practice requisite to 

 become even a skilful pigeon-fancier. 



The same principles are followed by horticulturists ; 

 but the variations are here often more abrupt. No one 

 supposes that our choicest productions have been pro- 

 duced by a single variation from the aboriginal stock. 

 We have proofs that this has not been so in several 

 cases in which exact records have been kept ; thus, to 

 give a very trifling instance, the steadily -increasing size 

 of the common gooseberry may be quoted. We see 

 an astonishing improvement in many florists' flowers, 

 when the flowers of the present day are compared with 

 drawings made only twenty or thirty years ago. When 

 a race of plants is once pretty well established, the 

 seed-raisers do not pick out the best plants, but merely 

 go over their seed-beds, and pull up the " rogues," as 

 they call the plants that deviate from the proper 

 standard. With animals this kind of selection is, in 

 fact, likewise followed ; for hardly any one is so care- 

 less as to breed from his worst animals. 



In regard to plants, there is another means of ob- 

 serving the accumulated effects of selection — namely, 

 by comparing the diversity of flowers in the different 

 varieties of the same species in the flower-garden ; the 

 diversity of leaves, pods, or tubers, or whatever part is 

 valued, in the kitchen-garden, in comparison with the 

 flowers of the same varieties ; and the diversity of fruit 

 of the same species in the orchard, in comparison with 

 the leaves and flowers of the same set of varieties. 

 See how different the leaves of the cabbage are, and 

 how extremely alike the flowers ; how unlike the 

 flowers of the heartsease are, and how alike the leaves • 

 how much the fruit of the different kinds of goose- 



