ARTIFICIAL SELECTION 41 



Yet a remarkable number of new kinds of creatures 

 are known to have arisen in this way, and their diver- 

 sity is no less astonishing, as a visit to any great show 

 of domestic plants or animals will at once demonstrate. 

 Here may be seen varieties of pigeons, for example, 

 like the carrier, pouter, fantail, and tumbler, which, 

 if they were found existing in a wild condition, would 

 be placed in separate genera by any ornithologist. 

 The domestic races of fowls, dogs, horses, sheep, and 

 cattle show scarcely less divergence, and modifications 

 no less remarkable have been perpetuated in the case 

 of many cultivated species of plants. Whilst these 

 types have survived, being deliberately preserved on 

 account of their use or beauty or curious appearance, a 

 still greater number have doubtless been exterminated, 

 either because they did not attract the breeder's 

 favourable attention, or on account of their having 

 passed out of fashion. 



Darwin sought in Nature a substitute for the baleful 

 judgment of the breeder, and found it in an extension 

 of the Malthusian doctrine to organic beings in general. 

 The idea which is identified with this expression 

 did not, however, originate with Malthus, nor does 

 that author claim it as his own, as the following extract 

 from the first chapter of the ' Essay on Population ' 

 will show : 



' It is observed by Dr. Franklin that there is no bound 

 to the prolific nature of animals and plants but what 

 is made by their crowding and interfering with each 

 other's means of subsistence. Were the face of the 

 earth, he says, vacant of other plants,_it might be 



