VABIATION UNDER DOMESTICATION 51 



SI laller Britisl: islets, or on the chores of the Mediter- 

 ranean. Hence the supposed extermination of so many 

 species having similar habits with the rock-pigeon seems 

 a very rash assumption. Moreover, the several above- 

 named domesticated breeds have been transported to all 

 parts of the world, and, therefore, some of them must 

 have been carried back again into their native country; 

 but not one has become wild or feral, though the 

 dovecot-pigeon, which is the rock-pigeon in a very 

 slightly altered state, has become feral in several places. 

 Again, all recent experience shows that it is difficult to 

 get wild animals to breed freely under domestication; yet 

 on the hypothesis of the multiple origin of our pigeons, 

 it must be assumed that at least seven or eight species 

 were so thoroughly domesticated in ancient times by 

 half-civilized man as to be quite prolific under confine- 

 ment. 



Au argument of great weight, and applicable in sev- 

 eral other cases, is, that the above-specified breeds, though 

 agreeing generally with the wild rock-pigeon in constitu- 

 tion, habits, voice, coloring, and in most parts of their 

 structure, yet are certainly highly abnormal in other 

 parts; we may look in vain through the whole great 

 family of Columbidae for a beak like that of the English 

 carrier, or that of the short-faced tumbler, or barb; for 

 reversed feathers like those of the Jacobin; for a crop 

 like that of the pouter; for tail-feathers like those of 

 the fantail. Hence it must be assumed not only that 

 half-civilized man succeeded in thoroughly domesticating 

 several species, but that he intentionally or by chance 

 picked out extraordinarily abnormal species; and further, 

 that these very species have since all become extinct or 



