Origin of Species Variorum

→ natural and artificial, 1859 1860 1861

those naturally and those artificially produced, 1866 1869 1872

→ is probably 1859 1860 1861

has at some periods probably been 1866 1869 1872

→ the number of species has 1859 1860 1861

species have 1866 1869 1872

→ I. e. 1860 1861

i . e . 1859

i.e. 1866 1869 1872

and the consequent extinction of

the less-favoured

less-favoured

forms almost inevitably follows. It is the same with our domestic

productions;

productions:

when a new and slightly improved variety has been raised, it at first

generally supplants

supplants

the less improved varieties in the same neighbourhood; when much improved it is transported far and near, like our short-horn cattle, and takes the place of other breeds in other countries. Thus the appearance of new forms and the disappearance of old forms, both →natural and artificial, are bound together. In

~~certain~~

certain

flourishing groups, the number of new specific forms which have been produced within a given time →is probably greater than

the number

that

of the old

forms

specific forms

which have been exterminated; but we know that →the number of species has not gone on indefinitely increasing, at least during the later geological

epochs,

periods,

that,

that

looking to later

times,

times

we may believe that the production of new forms has caused the extinction of about the same number of old forms.

The competition will generally be most severe, as formerly explained and illustrated by examples, between the forms which are most like each other in all respects. Hence the improved and modified descendants of a species will generally cause the extermination of the parent-species; and if many new forms have been developed from any one species, the nearest allies of that species, → I. e. the species of the same genus, will be the most liable to extermination. Thus, as I believe, a number of new species descended from one species, that is a new genus, comes to supplant an old genus, belonging to the same family. But it must often have happened that a new species belonging to some one group

has

will have

seized on the place occupied by a species belonging to a distinct group, and thus

caused

have caused

cause

its

examination;

extermination.

extermination;

and if

any

many

allied forms be developed from the

successful

success-