destroyed by frost, and then collect seed from the few survivors, with care to prevent accidental crosses, and then again get seed from these seedlings, with the same precautions, the experiment cannot be said to have been even
tried. Nor let it be supposed that no
differences in the constitution of seedling kidney-beans ever
appear, for an account has been published how much more hardy some seedlings
appeared to be appeared to be 1859 1860 1861 |
were 1866 1869 |
are 1872 |
than
others. others. 1859 1860 1861 |
others; and of this fact I have myself observed a striking instance. 1866 |
others; and of this fact I have myself observed striking instances. 1869 1872 |
|
On the whole, I think
we may conclude that habit, use,
and disuse, have, in some cases, played a considerable part in the modification of the constitution,
and of the structure of various organs;
but that the effects of use and disuse
have often been largely combined with, and sometimes overmastered
by by 1860 1861 | by, 1859 1866 1869 1872 |
the natural selection of innate differences.
|
I mean by this expression that the whole organisation is so tied together during its growth and development, that when slight variations in any one part occur, and are accumulated through natural selection, other parts become modified.
This is a very important subject, most imperfectly understood. This is a very important subject, most imperfectly understood. 1859 1861 |
The most obvious case is, that modifications accumulated solely for the good of the young or larva, will, it may safely be concluded, affect the structure of the adult; in the same manner as any malconformation affecting the early embryo, seriously affects the whole organisation of the adult. 1860 |
This is a very important subject, most imperfectly understood, and no doubt totally different classes of facts may be here easily confounded together: we shall presently see that simple inheritance often gives the false appearance of correlation. 1866 1869 |
This is a very important subject, most imperfectly understood, and no doubt wholly different classes of facts may be here easily confounded together. 1872 |
↑1 blocks not present in 1859 1860 1861 1866 1869; present in 1872 | We shall presently see that simple inheritance often gives the false appearance of correlation.
|
The
most obvious case is, that modifications accumulated solely for the good of most obvious case is, that modifications accumulated solely for the good of 1859 1861 |
several parts of 1860 |
most obvious instance of real correlation is, that variations of structure arising in 1866 1869 |
most obvious real cases is, that variations of structure arising in 1872 |
the
young or larva, will, it may safely be concluded, affect the structure of the adult; in the same manner as any malconformation affecting the early embryo, seriously affects the whole organisation of the adult. young or larva, will, it may safely be concluded, affect the structure of the adult; in the same manner as any malconformation affecting the early embryo, seriously affects the whole organisation of the adult. 1859 1861 |
body which are homologous, and which, at an early embryonic period, are alike, seem liable to vary in an allied manner: we see this in the right and left sides of the body varying in the same manner; in the front and hind legs, and even in the jaws and limbs, varying together, for the lower jaw is believed to be homologous with the limbs. 1860 |
young or in the larvæ naturally tend to affect the structure of the mature animal; in the same manner as any malconformation in the early embryo is known seriously to affect the whole organisation of the adult. 1866 1869 |
young or larvæ naturally tend to affect the structure of the mature animal. 1872 |
The several parts of the body which are homologous, and which, at an early embryonic period, are
alike, seem alike, seem 1859 1861 |
identical in structure, and which are necessarily exposed to similar conditions, seem eminently 1866 1869 |
identical in structure, and which are neces- sarily exposed to similar conditions, seem eminently 1872 |
liable to vary
|