Evidences of Theory of Natural Selection. 295 
have been perfected by such an indirect agency of 
natural selection as is here suggested }. 
The third general class of facts which tell so im- 
mensely in favour of natural selection as an important 
cause of organic evolution, are those of domestication. 
The art of the horticulturist, the fancier, the cattle- 
breeder, &c., consists in producing greater and greater 
deviations from 4 given wild type of plant or animal, 
in any particular direction that may be desired for 
purposes either of use or of beauty. Cultivated 
cereals, fruits, and flowers are known to have been 
all derived from wild species ; and, of course, the same 
applies to all our domesticated varieties of animals. 
Yet if we compare a cabbage rose with a wild rose. a 
golden pippin apple with a crab, a toy terrier with any 
species of wild dog, not to mention any number of other 
instances, there can be no question that, if such differ- 
ences had appeared in nature, the organisms presenting 
them would have been entitled to rank as distinct 
species—or even, in many cases, as distinct genera. 
Yet we know, as a matter of fact, that all these 
differences have been produced by a process of arti- 
ficial selection, or pairing, which has been continuously 
practised by horticulturists and breeders through a 
number of generations. It is the business of these men 
to note the individual organisms which show most 
variation in the directions required, and then to 
propagate from these individuals, in order that the 
progeny shall inherit the qualities desired. The 
results thus become cumulative from generation to 
generation, until we now have an astonishing mani- 
1 Note B. 
