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1872

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→ on 1859 1860 1861 1866 1869
is intelligible on 1872
→ by considering the medium in which terrestrial animals live, and 1859 1860 1861 1866 1869
for owing to 1872
→ for we know of 1859 1860 1861 1866 1869
there are 1872
→ in the case of 1859 1860 1861 1866 1869
with 1872
→ currents in the 1859 1860 1861 1866 1869
the currents of 1872
→ case of an 1859 1860 1861 1866 1869
OMIT 1872
→ within the body, 1859 1860 1861 1866 1869
OMIT 1872
→ a case of very great difficulty 1859 1860 1861 1866 1869
OMIT 1872
→ but 1859 1860 1861 1866 1869
a case of great difficulty; but 1872
→ in the case of both 1859 1860 1861 1866 1869
both with 1872
→ not rarely, some of them 1859 1860 1861 1866 1869
OMIT 1872
→ with other individuals, 1859 1860 1861 1866 1869
OMIT 1872
→ I am strongly inclined to suspect, that, both in the vegetable and animal kingdoms, 1866 1869
I am strongly inclined to suspect that, both in the vegetable and animal kingdoms, 1859 1860 1861
it appears that with animals and plants 1872
→on the view of an occasional cross being
indispensable;
indispensable,
→by considering the medium in which terrestrial animals live, and the nature of the fertilising
element
element;
→for we know of no means, analogous to the action of insects and of the wind →in the case of plants, by which an occasional cross could be effected with terrestrial animals without the concurrence of two individuals. Of aquatic animals, there are many self-fertilising hermaphrodites; but here →currents in the water offer an obvious means for an occasional cross.
As
And, as
in the case of flowers, I have as yet failed, after consultation with one of the highest authorities, namely, Professor Huxley, to discover a single →case of an hermaphrodite animal with the organs of reproduction so perfectly enclosed →within the body, that access from
without,
without
and the occasional influence of a distinct
individual,
individual
can be shown to be physically impossible. Cirripedes long appeared to me to
present,
present
→a case of very great difficulty under this point of
view,
view;
→but I have been enabled, by a fortunate chance,
elsewhere
elsewhere
to prove that two individuals, though both are self-fertilising hermaphrodites, do sometimes cross.
It must have struck most naturalists as a strange anomaly that, →in the case of both animals and plants,
some species
species
of the same family and even of the same genus, though agreeing closely with each other in
almost
almost
their whole organisation,
yet
yet
are →not rarely, some of them hermaphrodites, and some
of them
of them
unisexual. But if, in fact, all hermaphrodites do occasionally
intercross,
intercross
→with other individuals, the difference between
them
hermaphrodites
and unisexual
species
species,
is, as
as
far as function is concerned,
becomes
becomes
very small.
From these several considerations and from the many special facts which I have collected, but which I am
unable
not
here
able
able
to give, →I am strongly inclined to suspect, that, both in the vegetable and animal kingdoms, an