Origin of Species Variorum

→ plant. 1859 1860 1861

plants in each great class on a uniformly regulated plan: but this is not a scientific explanation. 1866

plants in each great class on a uniform plan; but this is not a scientific explanation. 1869 1872

→ manifest 1859 1860 1861 1866 1869

to a large extent simple 1872

→ and become gradually 1859 1860 1861 1866

becoming at the same time 1869 1872

→ to any extent, 1859 1860 1861 1866

OMIT 1869 1872

→ this great amount of modification there will be no tendency 1859 1860 1861

this great amount of modification there would be no tendency 1866

this modification would not tend 1869

these modifications would not tend 1872

→ the ancient progenitor, 1859 1860 1861 1866

an early progenitor,— 1869

an early progenitor— 1872

→ had 1859 1860 1861 1866 1869

birds, and reptiles, had 1872

→ will 1859 1861 1866 1869 1872

acting on some originally created form, will 1860

creation of each being, we can only say that so it is;— that it has

pleased the Creator to construct

all the

each

animals

animal

and →plant.

The explanation is →manifest

according to

the theory of the

~~natural~~

natural

selection of successive slight modifications,— each modification being profitable in some way to the modified form, but often affecting by correlation

~~of growth~~

of growth

other parts of the organisation. In changes of this nature, there will be little or no tendency to

modifiy

alter

modify

the original pattern, or to transpose

the parts.

parts.

The bones of a limb might be shortened and

flattened

widened

to any extent, →and become gradually enveloped in thick membrane, so as to serve as a fin; or a webbed

hand

foot

might have all its bones, or certain

bones,

bones

lengthened to any extent,

with

and

the membrane connecting them

increased,

increased

→to any extent, so as to serve as a

wing:

wing;

yet

all →this great amount of modification there will be no tendency to alter the framework of

the bones

bones

or the relative connexion of the

~~several~~

several

parts. If we suppose that →the ancient progenitor, the archetype as it may be

called,—

called—

called,

of all mammals, →had its limbs constructed on the existing general pattern, for whatever purpose they served, we can at once perceive the plain signification of the homologous construction of the limbs throughout the

~~whole~~

whole

class. So with the mouths of insects, we have only to suppose that their common progenitor had an upper lip, mandibles, and two

pairs

pair

of maxillæ, these parts being perhaps very simple in form; and then natural

selection,

selection

→will account for the infinite diversity in

the structure

structure

and

functions

function

of the mouths of insects. Nevertheless, it is conceivable that the general pattern of an organ might become so much obscured as to be finally lost, by the

reduction

atrophy

and ultimately by the complete abortion of certain parts, by the

fusion

soldering together

of other parts, and by the doubling or multiplication of others,—

variations

varia- tions