Origin of Species Variorum

→ may often have 1869

will probably often 1859 1860 1861 1866

→ aided in 1869

this will tend to cause 1859 1860 1861 1866

↑ 7 blocks not present in 1859 1860 1861 1866 1869; present in 1872

There remains, however, this difficulty. After an organ has ceased being used, and has become in consequence much reduced, how can it be still further reduced in size until the merest vestige is left; and how can it be finally quite obliterated? It is scarcely possible that disuse can go on producing any further effect after the organ has once been rendered functionless. Some additional explanation is here requisite which I cannot give. If, for instance, it could be proved that every part of the organisation tends to vary in a greater degree towards diminution than towards augmentation of size, then we should be able to understand how an organ which has become useless would be rendered, independently of the effects of disuse, rudimentary and would at last be wholly suppressed; for the variations towards diminished size would no longer be checked by natural selection. The principle of the economy of growth, explained in a former chapter, by which the materials forming any part, if not useful to the possessor, are saved as far as is possible, will perhaps come into play in rendering a useless part rudimentary. But this principle will almost necessarily be confined to the earlier stages of the process of reduction; for we cannot suppose that a minute papilla, for instance, representing in a male flower the pistil of the female flower, and formed merely of cellular tissue, could be further reduced or absorbed for the sake of economising nutriment.

→ As the presence of 1859 1860 1861 1866 1869

Finally, as 1872

→ is thus due to the tendency in every part of the organisation, which has long existed, to be 1859 1860 1861 1866 1869

by whatever steps they may have been degraded into their present useless condition, are the record of a former state of things, and have been retained solely through the power of 1872

→ have 1859 1860 1861 1866 1869

in placing organisms in their proper places in the natural system, have often 1872

→ in accordance with the views here explained. 1869 1872

and can be accounted for by the laws of inheritance. 1859 1860 1861 1866

→ all organic beings 1869 1872

group to group in all organisms 1859 1860 1861

group to group in all organic beings 1866

→ in group under group— that 1869

that 1859 1860 1861 1866

in groups under groups— that 1872

→ in a few grand classes,— 1869

into one grand system; 1859 1860 1861 1866

into a few grand classes,— 1872

→ or 1869

vital importance, or of 1859 1860 1861 1866

or of 1872

if not useful to the possessor, will be saved as far as is possible, →may often have come into

play;

play,

and →aided in the entire obliteration of a rudimentary organ. ↑

→As the presence of rudimentary

organs,

organs

→is thus due to the tendency in every part of the organisation, which has long existed, to be

inheritance,—

inherited—

we can understand, on the genealogical view of classification, how it is that

systematists,

systematists

→have found rudimentary parts as useful as, or even sometimes more useful than, parts of high physiological importance. Rudimentary organs may be compared with the letters in a word, still retained in the spelling, but become useless in the pronunciation, but which serve as a clue

in seeking

....

for its derivation. On the view of descent

with

with,

modification, we may conclude that the existence of organs in a rudimentary, imperfect, and useless condition, or quite aborted, far from presenting a strange difficulty, as they assuredly do on the

old

ordinary

doctrine of creation, might even have been

anticipated,

anticipated

→in accordance with the views here explained.

Summary .—

Summary .

In this chapter I have attempted to show, that the

subordination

arrangement

of →all organic beings throughout all

time;

time

→in group under group— that the nature of the

relationships

relationship,

by which all living and extinct

beings

organisms

are united by complex, radiating, and circuitous lines of affinities →in a few grand classes,— the rules followed and the difficulties encountered by naturalists in their

classifications;

classifications,—

the value set upon characters, if constant and prevalent, whether of high →or the most trifling importance, or, as

with

rudimentary organs, of no

importance;

importance,—

the wide opposition in value between analogical or adaptive characters, and characters of true affinity; and other