VARIATION UNDER DOMESTICATION 35 



seldom produce young; whereas carnivorous birds, with 

 the rarest exceptions, hardly ever lay fertile eggs. Many 

 exotic plants have pollen utterly worthless, in the same 

 condition as in the most sterile hybrids. When, on the 

 one hand, we see domesticated animals and plants, though 

 often weak and sickly, breeding freely under confine- 

 ment; and when, on the other hand, we see individuals, 

 though taken young from a state of nature perfectly 

 tamed, long-lived and healthy (of which I could give 

 numerous instances), yet having their reproductive sys- 

 tem so seriously affected by unperceived causes as to fail 

 to act, we need not be surprised at this system, when it 

 does act under confinement, acting irregularly, and pro- 

 ducing offspring somewhat unlike their parents. I may 

 add that as some organisms breed freely under the most 

 unnatural conditions (for instance, rabbits and ferrets 

 kept in hutches), showing that their reproductive organs 

 are not easily affected; so will some animals and plants 

 withstand domestication or cultivation, and vary very 

 slightly — perhaps hardly more than in a state of nature. 



Some naturalists have maintained that all variations 

 are connected with the act of sexual reproduction; but 

 this is certainly an error; for I have given in another 

 work a long list of "sporting plants," as they are called 

 by gardeners; — that is, of plants which have suddenly 

 produced a single bud with a new and sometimes widely 

 different character from that of the other buds on the 

 same plant. These bud variations, as they may be 

 named, can be propagated by grafts, offsets, etc., and 

 sometimes by seed. They occur rarely under nature, but 

 are far from rare under culture. As a single bud out of 

 the many thousands, produced year after year on the 



