30 SELECTION BY MAN. Chap. I. 



is that we see in them adaptation, not indeed to the 

 animal's or plant's own good, but to man's use or fancy. 

 Some variations useful to him have probably arisen 

 suddenly, or by one step ; many botanists, for instance, 

 believe that the fuller's teazle, with its hooks, which 

 cannot be rivalled by any mechanical contrivance, is 

 only a variety of the wild Dipsacus ; and this amount of 

 change may have suddenly arisen in a seedling. So it 

 has probably been with the turnspit dog ; and this is 

 known to have been the case with the ancon sheep. But 

 when we compare the dray-horse and race-horse, the 

 dromedary and camel, the various breeds of sheep fitted 

 either for cultivated land or mountain pasture, with the 

 wool of one breed good for one purpose, and that of 

 another breed for another purpose ; when we compare 

 the many breeds of dogs, each good for man in very 

 different ways ; when we compare the game-cock, so 

 pertinacious in battle, with other breeds so little quarrel- 

 some, with " everlasting layers " which never desire to 

 sit, and with the bantam so small and elegant; when 

 we compare the host of agricultural, culinary, orchard, 

 and flower-garden races of plants, most useful to man at 

 different seasons and for different purposes, or so beau- 

 tiful in his eyes, we must, I think, look further than to 

 mere variability. We cannot suppose that all the breeds 

 were suddenly produced as perfect and as useful as we 

 now see them ; indeed, in several cases, we know that 

 this has not been their history. The key is man's power 

 of accumulative selection : nature gives successive varia- 

 tions; man adds them up in certain directions useful to 

 him. In this sense he may be said to make for himself 

 useful breeds. 



The great power of this principle of selection is not 

 hypothetical. It is certain that several of our eminent 

 breeders have, even within a single lifetime, modified to 



