VARIATION UNDER DOMESTICATION 9 



the plantigrades or bear family ; whereas carnivoious 

 birds, with the rarest exceptions, hardly ever lay fertile 

 eggs. Many exotic plants have pollen utterly worthless, 

 in the same exact condition as in the most sterile hybrids. 

 When, on the one hand, we see domesticated animals 

 and plants, though often weak and sickly, yet breeding 

 quite freely under confinement ; 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 system so seriously affected by un- 

 perceived causes as to fail in acting, we need not be 

 surprised at this system, when it does act under con- 

 finement, acting not quite regularly, and producing off- 

 spring not perfectly like their parents. 



Sterility has been said to be the bane of horticulture ; 

 but on this view we owe variability to the same cause 

 which produces sterility ; and variability is the source 

 of all the choicest productions of the garden. I may 

 add, that as some organisms will breed freely under 

 the most unnatural conditions (for instance, the rabbit 

 and ferret kept in hutches), showing that their repro- 

 ductive system has not been thus affected ; so will some 

 animals and plants withstand domestication or cultiva- 

 tion, and vary very slightly — perhaps hardly more than 

 in a state of nature. 



A long list could easily be given of ' sporting plants ' ; 

 by this term gardeners mean a single bud or offset, 

 which suddenly assumes a new and sometimes very 

 different character from that of the rest of the plant. 

 Such buds can be propagated by grafting, etc., and 

 sometimes by seed. These f sports' are extremely 

 rare under nature, but far from rare under cultivation ; 

 and in this case we see that the treatment of the parent 

 has affected a bud or offset, and not the ovules or pollen. 

 But it is the opinion of most physiologists that there is no 

 essential difference between a bud and an ovule in their 

 earliest stages of formation ; so that, in fact, ( sports ' 

 support my view, that variability may be largely attri- 

 buted to the ovules or pollen, or to both, having been 



