There is another and equally curious branch of
our present | our present 1869 | | the present 1859 1860 1861 1866 | | our 1872 |
subject; namely, the comparison not
of the same
parts | parts 1869 1872 | | part 1859 1860 1861 1866 |
or organs in different members of the same class, but | or organs in different members of the same class, but 1869 |
| in different members of a class, but 1859 1860 1861 |
| or organ in different members of the same class, but 1866 |
| or organs in the same individual, and not 1872 |
of the different
parts or organs in the same individual. Most physiologists believe that the bones of the skull are homologous with—
that
is, | is, 1866 1869 1872 | | is 1859 1860 1861 |
correspond in number and in relative connexion with—
the
elemental parts of a certain number of vertebræ. The anterior and posterior limbs in
all the higher vertebrate | all the higher vertebrate 1869 1872 |
| each member of the vertebrate and articulate 1859 1860 1861 |
| all the members of the vertebrate 1866 |
classes are plainly homologous.
So it is with | So it is with 1866 1869 1872 |
| We see the same law in comparing 1859 1860 1861 |
the wonderfully complex jaws and legs
of | of 1866 1869 1872 | | in 1859 1860 1861 |
crustaceans. It is familiar to almost every one, that in a flower the relative position of the sepals, petals, stamens, and pistils, as well as their intimate structure, are intelligible on the view that they consist of metamorphosed leaves, arranged in a spire. In monstrous plants, we often get direct evidence of the possibility of one organ being transformed into another; and we can actually
see, | see, 1869 1872 | | see 1859 1860 1861 1866 |
during the early or embryonic stages of development in flowers, | during the early or embryonic stages of development in flowers, 1869 1872 |
| in embryonic crustaceans and in many other animals, and in flowers, 1859 1860 1861 |
| in flowers during their early development, as well as in crustaceans and many other animals during their embryonic states, 1866 |
as well as in crustaceans and many other animals, that | as well as in crustaceans and many other animals, that 1869 1872 |
| that 1859 1860 1861 1866 |
organs, which when mature become extremely different,
are at
first | first 1869 1872 |
| an early stage of growth 1859 1860 1861 1866 |
exactly alike. |