Chap. I. UNDEIl DOMESTICATIOin. 25 



instances), yet having their reproductive system so seriously 

 anccted by uiiperceived causes as to fail to act, Ave need not 

 he surprised at this system, when it does act under confine- 

 UKMit, acting irregularly, and jiroducing offspring' somewhat 

 imlike their parents. I may adil, that as some organisms breed 

 fn^ely under the most unnatural conditions (for instance, rali- 

 bits and ferrets kept in hutches), showing that their reproduc- 

 tive organs arc not 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 cer- 

 tainly an eiTor; for I have given in another woi'k 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-diilerent 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 far 

 from rarely under culture. As a single bud out of the manj^ 

 thousands produced year after year under uniform conditions 

 on the same tree, has been known suddenly to assmne a new 

 character ; and as buds on distinct trees growing und(^r differ- 

 ent conditions, have sometimes yielded nearly the same variety 

 — for instance, buds on peach-trees producing nectarines, and 

 buds on common roses producing moss-roses — we clearly see 

 tliat the nature of the conditions is of quite subordinate impor- 

 tance in comparison with the nature of the organism in deter- 

 mining each particular form of variation — of not more impor- 

 tance than the nature of the spark by wliich a mass of combus- 

 t \h\o matter is ignited, has in determining the nature of the 

 flames. 



Effects of Habit ; Correlated Variation / Inheritance. 



Habits are inherited and have a decided influence ; as in 

 the period of the flowering of plants when transported from 

 one climate to another. In animals they have a more marktnl 

 effect ; for instance, I llnd in the domestic duck that the bones 

 of the wing weigh less and the bones of the leg more, in pro- 

 portion to the whole skeleton, than do the same bones in the 

 wild-duck ; and this change may be safely attributed to the do- 

 mestic duck flying mucli less, and walking more, than its Mild 

 ]):irents. The great and inherite<l development of the udders 



