Comparison with 1861 |
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axiom "of least action" leads the mind more willingly to admit the smaller number; and certainly we ought not to believe that innumerable beings within each great class have been created with plain, but deceptive, marks of descent from a single parent. ↑1 blocks not present in 1861 1866 1869 1872; present in 1859 1860 | Although naturalists very properly demand a full explanation of every difficulty from those who believe in the mutability of species, on their own side they ignore the whole subject of the first appearance of species in what they consider reverent silence.
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It may be asked how far I extend the doctrine of the modification of species. The question is difficult to answer, because the more distinct the forms are which we
may may 1859 1860 1861 1866 | may 1869 1872 |
consider, by so much the arguments fall away
in force. But some arguments of the greatest weight extend very far. All the members of whole classes
can be can be 1859 1860 1861 1866 | are 1869 1872 |
connected together by
chains chains 1859 1860 1861 1866 | a chain 1869 1872 |
of affinities, and all can be classified
on the same principle, in groups
sub-ordinate sub-ordinate 1861 | subordinate 1859 1860 1866 1869 1872 |
to groups. Fossil remains sometimes tend to fill up very wide intervals between existing orders. Organs in a rudimentary condition plainly show that an early progenitor had the organ in a fully developed state;
and this in some
instances necessarily instances necessarily 1859 1860 1861 1866 | instances 1869 | cases 1872 |
implies an enormous amount of modification in the descendants. Throughout whole classes various structures are formed on the same pattern, and at
an embryonic an embryonic 1859 1860 1861 1866 |
a very early 1869 1872 |
age the
species species 1859 1860 1861 1866 | embryos 1869 1872 |
closely resemble each other. Therefore I cannot doubt that the theory of descent with modification embraces all the members of the same class. I believe that animals
have have 1859 1860 1861 1866 | are 1869 1872 |
descended from at most only four or five progenitors, and plants from an equal or lesser number. |
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Analogy would lead me one step further,
namely, to the belief that all animals and plants
have have 1859 1860 1861 1866 | are 1869 1872 |
descended from some one prototype. But analogy may be a deceitful guide. Nevertheless all living things have much in common,
in their chemical composition, their germinal vesicles, their
cellular structure, and
their laws of growth
and reproduction. We see this even in so trifling a
circumstance circumstance 1859 1860 1861 1866 | fact 1869 1872 |
as that the same poison often similarly affects plants
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axiom "of least action" leads the mind more willingly to admit the smaller number; and certainly we ought not to believe that innumerable beings within each great class have been created with plain, but deceptive, marks of descent from a single parent. ↑1 blocks not present in 1861 1866 1869 1872; present in 1859 1860 | Although naturalists very properly demand a full explanation of every difficulty from those who believe in the mutability of species, on their own side they ignore the whole subject of the first appearance of species in what they consider reverent silence.
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It may be asked how far I extend the doctrine of the modification of species. The question is difficult to answer, because the more distinct the forms are which we
....... 1869 1872 | may 1859 1860 1861 1866 |
consider, by so much the arguments
fall away fall away 1859 1860 1861 1866 1869 |
in favour of community of descent become fewer in number and less 1872 |
in force. But some arguments of the greatest weight extend very far. All the members of whole classes
are are 1869 1872 | can be 1859 1860 1861 1866 |
connected together by
a chain a chain 1869 1872 | chains 1859 1860 1861 1866 |
of affinities, and all can be
classified classified 1859 1860 1861 1866 1869 | classed 1872 |
on the same principle, in groups
subordinate subordinate 1859 1860 1866 1869 1872 | sub-ordinate 1861 |
to
groups. groups. 1859 1860 1861 1866 1869 |
groups. Fossil remains sometimes tend to fill up very wide intervals between existing orders.
1872 |
Fossil remains sometimes tend to fill up very wide intervals between existing orders. Organs in a rudimentary condition plainly show that an early progenitor had the organ in a fully developed
state; state; 1859 1860 1861 1866 1869 | condition; 1872 |
and this in some
instances instances 1869 | instances necessarily 1859 1860 1861 1866 | cases 1872 |
implies an enormous amount of modification in the descendants. Throughout whole classes various structures are formed on the same pattern, and at
a very early a very early 1869 1872 |
an embryonic 1859 1860 1861 1866 |
age the
embryos embryos 1869 1872 | species 1859 1860 1861 1866 |
closely resemble each other. Therefore I cannot doubt that the theory of descent with modification embraces all the members of the same
class. class. 1859 1860 1861 1866 1869 |
great class or kingdom. 1872 |
I believe that animals
are are 1869 1872 | have 1859 1860 1861 1866 |
descended from at most only four or five progenitors, and plants from an equal or lesser number. |
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Analogy would lead me one step
farther, farther, 1861 1866 1869 1872 | further, 1859 1860 |
namely, to the belief that all animals and plants
are are 1869 1872 | have 1859 1860 1861 1866 |
descended from some one prototype. But analogy may be a deceitful guide. Nevertheless all living things have much in
common,— common,— 1861 1866 1869 | common, 1859 1860 1872 |
in their chemical composition, their
...OMIT 1861 1866 1869 1872 |
germinal vesicles, their 1859 1860 |
cellular structure,
....... 1861 1866 1869 1872 | and 1859 1860 |
their laws of
growth, growth, 1861 1866 1869 1872 | growth 1859 1860 |
and
their liability to injurious influences. their liability to injurious influences. 1861 1866 1869 1872 |
reproduction. 1859 1860 |
We see this even in so trifling a
fact fact 1869 1872 | circumstance 1859 1860 1861 1866 |
as that the same poison often similarly affects plants
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