this curious subject; but to show how singular the laws are which determine the reproduction of animals under confinement, I may
just | just 1859 1860 1861 1866 | just 1869 1872 |
| family, 1861 1866 1869 1872 | | family; 1859 1860 |
| which seldom produce young; whereas 1861 1866 1869 1872 |
| whereas, 1859 |
| whereas 1860 |
| exact 1859 1860 1861 1866 | exact 1869 1872 |
| yet 1859 1860 1861 1866 1869 | yet 1872 |
| quite 1859 1860 1861 1866 | quite 1869 1872 |
| nature, 1859 1860 1861 1866 1869 | | nature 1872 |
| long-lived, 1859 1860 1861 1866 1869 | | long-lived 1872 |
| in acting, 1859 1860 1861 1866 | | to act, 1869 1872 |
| not quite 1859 1860 1861 1866 | not quite 1869 1872 |
| regularly, 1859 1860 1861 1866 | | irregularly, 1869 1872 |
| not perfectly like 1859 1860 1861 1866 |
| somewhat unlike 1869 1872 |
| parents. 1860 1861 1866 1869 1872 | | parents 1859 |
| ..... 1860 1861 1866 1869 1872 | | or 1859 |
| ..... 1860 1861 1866 1869 1872 | | variable. 1859 |
| 5 blocks not present in 1859 1860 1861 1866; present in 1869 1872 | | 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 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, &c., and sometimes by seed.
They occur rarely under nature, but far from rarely
under culture.
As a single bud out of the
many thousands
produced year after year under uniform conditions on the same tree,
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 quite
subordinate importance in comparison with the nature of the organism in determining each particular form of variation; — of
not more importance than the nature of the spark
by which a mass of com-
bustible
matter is ignited, has in determining the nature of the flames.
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| Subtitle not present 1859 1860 1861 1866 1869 1872 |
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