I attempted also to show that there is a
constant constant 1859 1860 1861 1866 1869 | steady 1872 |
tendency in the forms which are increasing in number and diverging in character, to supplant and exterminate the
less divergent, the less divergent, the 1859 1860 1861 |
preceding, less divergent and 1866 1869 1872 |
less
improved, improved, 1859 1860 1861 | improved 1866 1869 1872 |
and preceding and preceding 1859 1860 1861 | and preceding 1866 1869 1872 |
forms. I request the reader to turn to the diagram illustrating the action, as formerly explained, of these several principles; and he will see that the inevitable result
is is 1859 1860 1861 1866 1869 | is, 1872 |
that the modified descendants proceeding from one progenitor become broken up into groups subordinate to groups. In the diagram each letter on the uppermost line may represent a genus including several species; and
all all 1859 1860 1861 1866 | all 1869 1872 |
the
genera on this genera on this 1859 1860 1861 1866 |
whole of the genera along this upper 1869 1872 |
line line 1859 1860 1869 1872 | upper line 1861 1866 |
form together one class, for all
have have 1859 1860 1861 1866 | are 1869 1872 |
descended from one ancient
but unseen but unseen 1859 1860 | but unseen 1861 1866 1869 1872 |
parent, parent, 1859 1860 1861 1866 | parent 1869 1872 |
and, consequently, have inherited something in common. But the three genera on the left hand have, on this same principle, much in common, and form a sub-family, distinct from that
including including 1859 1860 1861 1866 1869 | containing 1872 |
the next two genera on the right hand, which diverged from a common parent at the fifth stage of descent. These five genera have also
much, much, 1859 1860 1861 1866 1869 | much 1872 |
though less, in common; though less, in common; 1859 1860 1861 1866 1869 |
in common, though less than when grouped in sub-families; 1872 |
and they form a family distinct from that
including including 1859 1860 1861 1866 1869 | containing 1872 |
the three genera still
further further 1859 1860 | farther 1861 1866 1869 1872 |
to the right hand, which diverged at
a still a still 1859 1860 1861 1866 1869 | an 1872 |
earlier period. And all these genera,
descended descended 1859 1860 1866 1869 1872 | pescended 1861 |
from (A), form an order distinct from the
|