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;
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| rabbit |
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| ferret |
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, &c., and sometimes by seed.
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| graft |
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 same tree under uniform conditions, has been known suddenly to assume a new character; and as buds on distinct trees, growing under different 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 that the nature of the conditions is of subordinate importance in comparison with the nature of the organism in determining each particular form of variation;-
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| bud |
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| tree |
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| peach |
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| nectarine |
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| rose |
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| Moss Rose |
perhaps of not more importance than the nature of the spark, by which a mass of combustible matter is ignited, has in determining the nature of the flames.
