VARIATION UNDER DOMESTICATION 21 



tised before, has improved them astonishingly." About this same 

 period the Dutch were as eager about pigeons as were the old 

 Romans. The paramount importance of these considerations in ex- 

 plaining the immense amount of variation which pigeons have 

 undergone, will likewise be obvious when we treat of selection. We 

 shall then, also, see how it is that the several breeds so often have 

 a somewhat monstrous character. It is also a most favorable cir- 

 cumstance for the production of distinct breeds, that male and 

 female pigeons can be easily mated for life; and thus different 

 breeds can be kept together in the same aviary. 



I have discussed the probable origin of domestic pigeons at 

 some, yet quite insufficient, length; because when I first kept pi- 

 geons and watched the several kinds, well knowing how truly they 

 breed, I felt fully as much difficulty in believing that since they 

 had been domesticated they had all proceeded from a common 

 parent, as any naturalist could in coming to a similar conclusion 

 in regard to the many species of finches, or other groups of birds, 

 in nature. One circumstance has struck me much; namely, that 

 nearly all the breeders of the various domestic animals and the 

 cultivators of plants, with whom I have conversed, or whose 

 treatises I have read, are firmly convinced that the several breeds 

 to which each has attended, are descended from so many aborigi- 

 nally distinct species. Ask, as I have asked, a celebrated raiser of 

 Hereford cattle, whether his cattle might not have descended from 

 Long-horns, or both from a common parent-stock, and he will 

 laugh you to scorn. I have never met a pigeon, or poultry, or duck, 

 or rabbit fancier, who was not fully convinced that each main 

 breed was descended from a distinct species. Van Mons, in his 

 treatise on pears and apples, shows how utterly he disbelieves that 

 the several sorts, for instance, a Ribston-pippin or Codlin-apple, 

 could ever have proceeded from the seeds of the same tree. In- 

 numerable other examples could be given. The explanation, I 

 think, is simple: from long-continued study they are strongly im- 

 pressed with the differences between the several races ; and though 

 they well know that each race varies slightly, for they win their 

 prizes by selecting such slight differences, yet they ignore all gen- 

 eral arguments, and refuse to sum up in their minds slight differ- 

 ences accumulated during many successive generations. May not 

 those naturalists who, knowing far less of the laws of inheritance 

 than does the breeder, and knowing no more than he does of the 

 intermediate links in the long lines of descent, yet admit that 

 many of our domestic races are descended from the same parents — 

 may they not learn a lesson of caution, when they deride the idea 



