'22 SELECTION BY MAN. [CHAP. L 



times at intervals of months, and the sheep are each time marked 

 and classed, so that the very best may ultimately be selected for 

 breeding. 



What English breeders have actually effected is proved by the 

 enormous prices given for animals with a good pedigree ; and these 

 have been exported to almost every quarter of the world. The im- 

 provement is by no means generally due to crossing different 

 breeds ; all the best breeders are strongly opposed to this practice, 

 except sometimes amongst closely allied sub-breeds. And when a 

 cross has been made, the closest selection is far more indispensable 

 even than in ordinary cases. If selection consisted merely in sepa- 

 rating some very distinct variety, and breeding from it, the prin- 

 ciple would be so obvious as hardly to be worth notice ; but its 

 importance consists in the great effect produced by the accumula- 

 tion in one direction, during successive generations, of differences 

 absolutely inappreciable by an uneducated eye differences which 

 I for one have vainly attempted to appreciate. Not one man in a 

 thousand has accuracy of eye and judgment sufficient to become 

 an eminent breeder. If gifted with these qualities, and he studies 

 his subject for years, and devotes his lifetime to it with indomitable 

 perseverance, he will succeed, and may make great improvements ; 

 if he wants any of these qualities, he will assuredly fail. Few 

 would readily believe in the 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 produced 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 im- 

 provement 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 

 careless as to breed from his worst animals. 



In regard to plants, there is another means of observing the 

 accumulated effects of selection namely, by comparing the di- 

 versity 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 



