16 DARWIN'S THEORY. 



known as the Fantail, has been developed, since the 

 bird was taken from a state of nature. The oesophagus 

 has attained an enormous size, in the Pouter. A sur- 

 prisingly large beak marks the Carrier. A great quan- 

 tity of eye wattle has arisen, and now adorns the 

 Barb. Divergent, and large feathers, along the front 

 of the neck and breast, have appeared, where not even 

 a ruffled feather was discernible before, and distin- 

 guish the Turbit. The Jacobin has the feathers so 

 much reversed, along the back of the neck, that they 

 form a hood. These feathers, also, are absent in the 

 common bird, as found under nature. Other varieties 

 have, proportionally to their size, much elongated, or 

 much shortened, heads, necks, legs, tails, wings, bodies ; 

 and the proportions of the several characters, have 

 been so much varied, that almost every possible ratio 

 of the development of the species' characters, is to be 

 found among the several varieties. As in the case of 

 other animals, even the bones, and the internal organs, 

 have experienced a marked change in size, number, 

 and other characters. 



So great, in fact, has been the range of variation, in 

 this species, that, as Darwin truly remarks, a naturalist, 

 did he not know of the community of descent of these 

 varieties, would be induced to esteem many of them, 

 as distinct species, and a few of them, as even distinct 

 genera. 



Judging merely by structural differences, and ignor- 

 ing the physiological effect which the development or 

 reduction of a character, has upon organisms, there 

 are many other varieties, under domestication, which 



