Origin of Species Variorum

→ as they now exist, but 1869 1872

but 1859 1860 1861

in their present state, but 1866

→ and simpler element. 1866 1869 1872

element. 1859 1860 1861

→ this having 1869 1872

a modification of this nature having 1859 1860 1861

such modifications having actually 1866

→ According to the views here maintained, such language 1869 1872

On my view these terms 1859 1860 1861 1866

→ OMIT 1869 1872

during a long course of descent 1859 1860 1861 1866

→ though extremely simple legs, is in part 1872

legs, or from some simple appendage, is 1859 1860 1861

though simple legs, is 1866

though extremely simple legs, is 1869

→ subjects in the whole round 1869 1872

departments 1866

→ The 1872

Herein are included the ordinary 1866

→ familiar, are generally effected abruptly by a few stages; but the transformations are in reality numerous and gradual, though concealed. 1872

familiar. 1866

↑ 1 blocks not present in 1859 1860 1861 1872; present in 1866 1869

These are generally effected somewhat abruptly by a few stages and in a concealed manner; but the transformations are in reality numerous and graduated.

→ A 1869 1872

For instance, Sir J. Lubbock has recently shown that a 1866

→ as shown by Sir J. Lubbock, above 1869 1872

above 1866

→ and in this 1869 1872

in such 1866

→ performed in a primary and gradual manner. 1869 1872

in its natural or primary progress. 1866

adduces the close resemblance of the parts on the right and left sides of the body, and in the successive segments of the same individual animal; and here we have parts commonly called homologous, which bear no relation to the descent of distinct species from a common progenitor. Homoplastic structures are the same with those which I have classed, though in a very imperfect manner, as analogous modifications or resemblances. Their formation may be attributed in part to distinct organisms, or to distinct parts of the same organism, having varied in an analogous manner; and in part to similar modifications, having been preserved for the same general purpose or function,— of which many instances have been given.

Naturalists frequently speak of the skull as formed of metamorphosed

vertebræ:

vertebræ;

the jaws of crabs as metamorphosed legs; the stamens and pistils

flowers as metamorphosed leaves; but it would in

these

most

cases

probably

....

be more correct, as Professor Huxley has remarked, to speak of both skull and vertebræ,

both

....

jaws and legs,

&c.,—

&c.,

as having been metamorphosed, not one from the

other

other,

→as they now exist, but from some common →and simpler element.

Naturalists,

Most naturalists,

however, use such language only in a metaphorical

sense:

sense;

they are far from meaning that during a long course of descent, primordial organs of any kind— vertebræ in the one case and legs in the other— have actually been

modified

converted

into skulls or jaws. Yet so strong is the appearance of →this having occurred, that naturalists can hardly avoid employing language having this plain signification. →According to the views here maintained, such language may be used literally; and the wonderful fact of the jaws, for instance, of a crab retaining numerous characters, which they

would probably

probably would

have retained through inheritance, if they had really been metamorphosed →OMIT from true →though extremely simple legs, is in part explained.

Embryology

Development

and

Development .

Embryology .

Embryology.

This is one of the most important →subjects in the whole round of natural history. →The metamorphoses of insects, with which every one is →familiar, are generally effected abruptly by a few stages; but the transformations are in reality numerous and gradual, though concealed. ↑ →A certain ephemerous insect (Chlöeon) during its

development

development,

moults

moults,

→as shown by Sir J. Lubbock, above twenty times, and each time undergoes a certain amount of change; →and in this

cases

case

probably behold

see

the act of metamorphosis →performed in a primary and gradual manner. Many insects, and