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See page in:
1859
1860
1861
1866
1869
1872

Compare with:
1859
1860
1861
1869
1872

→ great 1866 1869
as is known to every one, great 1872
→ not directly connected with variability, 1866
independently of variation, 1872
OMIT 1869
→ as 1866
of various animals, 1869 1872
→ all 1866
many of the lower 1869 1872
→ however, other cases, namely 1866 1869
also, cases 1872
→ which might easily be, and have frequently been, confounded with variability, but which are really quite distinct. 1866
which might easily be, and have frequently been, confounded with variability, but which are quite distinct. 1869
both with animals and plants. 1872
→ Müller, also, has recently 1866 1869
Müller has 1872
→ widely different forms, not connected by any intermediate links; 1866 1869
distinct forms; 1872
→ for seizing the female, 1866 1869
OMIT 1872
→ as if for compensation, 1866 1869
OMIT 1872
↑ 6 blocks not present in 1859 1860 1861 1866 1869; present in 1872
Although in most of these cases, the two or three forms, both with animals and plants, are not now connected by intermediate gradations, it is probable that they were once thus connected. Mr. Wallace, for instance, describes a certain butterfly which presents in the same island a great range of varieties connected by intermediate links, and the extreme links of the chain closely resemble the two forms of an allied dimorphic species inhabiting another part of the Malay archipelago. Thus also with ants, the several worker-castes are generally quite distinct; but in some cases, as we shall hereafter see, the castes are connected together by finely graduated varieties. So it is, as I have myself observed, with some dimorphic plants. It certainly at first appears a highly remarkable fact that the same female butterfly should have the power of producing at the same time three distinct female forms and a male; and that an hermaphrodite plant should produce from the same seed-capsule three distinct hermaphrodite forms, bearing three different kinds of females and three or even six different kinds of males. Nevertheless these cases are only exaggerations of the common fact that the female produces offspring of two sexes which sometimes differ from each other in a wonderful manner.
not been seized on and rendered definite by natural selection, as hereafter
to
will
be explained.
Individuals of the same species often
present,
present
→great differences of structure, →not directly connected with variability, as in the two
sexes
sexes,
→as in the two or three castes of sterile females or workers amongst insects, and
as
as
in the immature and larval states of →all animals. There are, →however, other cases, namely of dimorphism and trimorphism, →which might easily be, and have frequently been, confounded with variability, but which are really quite distinct. I refer to the two or three
different
distinct
forms, which certain animals of either sex, and certain hermaphrodite plants, habitually present. Thus, Mr. Wallace, who has lately called
special
special
attention to the subject, has shown that the females of certain species of butterflies, in the Malayan archipelago, regularly appear under two or even three conspicuously distinct forms, not connected
together
together
by intermediate varieties. The winged and frequently wingless states of so many Hemipterous insects may probably be included as a case of dimorphism, and not of mere variability. Fritz →Müller, also, has recently described analogous but more extraordinary cases
with
in
the males of certain Brazilian Crustaceans: thus, the male of a Tanais regularly occurs under two →widely different forms, not connected by any intermediate links; one of these
forms
forms
has
much
much
strong
stronger
and differently shaped
pincers,
pincers
→for seizing the female, and the
other
other,
→as if for compensation, has antennæ much more abundantly furnished with
smelling-hairs.
smelling-hairs,
so
so
as
as
to
to
have
have
a
a
better
better
chance
chance
of
of
finding
finding
the
the
female.
female.
↑ Again, the males of another Crustacean, an Orchestia, occur under two distinct forms, with pincers differing much more from each other in structure, than do the pincers of most species of the same genus. With respect