64 THE ORIGIN OF SPECIES 



By a siinilur process of selection, intl by careful train* 

 ing, English racehorses have come to surpass in flectness 

 and size the parent Arabs, so that the latter, by the 

 regulations for the Goodwood Races, are favored in the 

 weights which they carry. Lord Spencer and others have 

 *i shown how the cattle of England have increased in 

 weight and in early maturity, compared with the stock 

 formerly kept in this country. By comparing the accounts 

 given in various old treatises of the former and present 

 state of carrier and tumbler pigeons in Britain, India and 

 Persia, we can trace the stages through which they have 

 insensibly passed, and come to differ so greatly from the 

 rock-pigeon. 



Youatt gives an excellent illustration of the effects of 

 a course of selection, which , may be considered as uncon- 

 scious, in so far that the breeders could never have 

 expected, or even wished, to produce the result which 

 ensued — namely, the production of two distinct strains. 

 The two flocks of Leicester sheep kept by Mr. Buckley 

 and Mr, Burgess, as Mr. Youatt remarks, "have been 

 purely bred from the original stock of Mr. Bakeweli for 

 upward of fifty years. There is not a suspicion existing 

 in the mind of any one at all acquainted with the subject 

 that the owner of either of them has deviated in any one 

 instance from the pure blood of Mr. Bakewell's flock, and 

 3'-et the difference between the sheep possessed by these 

 two gentlemen is so great that they have the appearance 

 of being quite different varieties." 



If there exist savages so barbarous as never to think 

 of the inherited character of the offspring of their domes- 

 tic animals, yet any one animal particularly useful to 

 them, for any special purpose, would be carefully pre- 



