Origin of Species Variorum

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

plant. 1859 1860 1861

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

→ to a large extent simple 1872

manifest 1859 1860 1861 1866 1869

→ becoming at the same time 1869 1872

and become gradually 1859 1860 1861 1866

→ OMIT 1869 1872

to any extent, 1859 1860 1861 1866

→ these modifications would not tend 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

→ an early progenitor— 1872

the ancient progenitor, 1859 1860 1861 1866

an early progenitor,— 1869

→ birds, and reptiles, had 1872

had 1859 1860 1861 1866 1869

→ will 1859 1861 1866 1869 1872

acting on some originally created form, will 1860

the curious folded one of a bee or bug, and the great jaws of a beetle? — yet all these organs, serving for such

dif- ferent

different

widely different

purposes, are formed by infinitely numerous modifications of an upper lip, mandibles, and two pairs of maxillæ.

Analogous

The same

laws

law

govern

governs

the construction of the mouths and limbs of crustaceans. So it is with the flowers of plants.

Nothing can be more hopeless than to attempt to explain this similarity of pattern in members of the same class, by utility or by the doctrine of final causes. The hopelessness of the attempt has been expressly admitted by Owen in his most interesting work on the 'Nature of Limbs.' On the ordinary view of the

inde- pendent

independent

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

....

pleased the Creator to construct

each

all the

animal

animals

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

The explanation is →to a large extent simple

according to

the theory of the

natural

....

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

of growth

....

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

modify

modifiy

alter

the original pattern, or to transpose

parts.

the parts.

The bones of a limb might be shortened and

widened

flattened

to any extent, →becoming at the same time enveloped in thick membrane, so as to serve as a fin; or a webbed

foot

hand

might have all its bones, or certain

bones

bones,

lengthened to any extent,

and

with

the membrane connecting them

increased

increased,

→OMIT so as to serve as a

wing:

wing;

yet

....

all →these modifications would not tend to alter the framework of

bones

the bones

or the relative connexion of the

several

....

parts. If we suppose that →an early progenitor— the archetype as it may be

called,

called,—

called—

of all mammals, →birds, and reptiles, 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

....

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

pair

pairs

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

selection,

selection

→will account for the infinite diversity in

structure

the structure

and

function

functions

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

atrophy

reduction

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

soldering together

fusion

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

varia- tions

variations

which we know to be within the limits of possibility. In the paddles of the

extinct gigantic

gigantic extinct

sea-lizards, and in the mouths of certain