Origin of Species Variorum

→ OMIT 1869 1872

to have been 1859 1860 1861 1866

→ have become partially 1872

a certain extent 1859 1860 1861 1866

have been partially 1869

→ serial homologies, or the comparison 1872

the comparison not 1859 1860 1861 1866 1869

→ or organs in the same individual, and not 1872

in different members of a class, but 1859 1860 1861

or organ in different members of the same class, but 1866

or organs in different members of the same class, but 1869

→ different members of the same class. 1872

the same individual. 1859 1860 1861 1866 1869

→ all the higher vertebrate 1869 1872

each member of the vertebrate and articulate 1859 1860 1861

all the members of the vertebrate 1866

→ So it is with 1866 1869 1872

We see the same law in comparing 1859 1860 1861

→ during the early or embryonic stages of development in flowers, 1869 1872

in embryonic crustaceans and in many other animals, and in flowers, 1859 1860 1861

in flowers during their early development, as well as in crustaceans and many other animals during their embryonic states, 1866

→ as well as in crustaceans and many other animals, that 1869 1872

that 1859 1860 1861 1866

→ first 1869 1872

an early stage of growth 1859 1860 1861 1866

→ the cases of serial homologies 1872

these facts 1859 1860 1861 1866 1869

→ bone, apparently representing vertebræ? 1872

bone? 1859 1860 1861 1866 1869

→ birds and reptiles. 1866 1869 1872

birds. 1859 1860 1861

→ to form 1869 1872

in the formation of 1859 1860 1861 1866

→ purposes, namely flying and walking? 1872

purposes? 1859 1860 1861 1866 1869

→ to a certain extent, 1872

satisfactorily 1859 1860 1861 1866

OMIT 1869

→ We need not here consider how the bodies of some animals first became divided into 1872

In the vertebrata, we see 1859 1860 1861 1866 1869

→ segments, or how they became 1872

internal vertebræ bearing certain processes and appendages; in the articulata, we see the body 1859 1860 1861 1866

internal vertebræ bearing certain processes; in the articulata, the body 1869

→ right and left sides, with corresponding organs, for such questions are almost beyond investigation. 1872

a series of segments, bearing external appendages; and in flowering plants, we see a series of successive spiral whorls of leaves. 1859 1860 1861 1866

a series of segments, bearing external appendages; and in flowering plants, spiral whorls of leaves. 1869

suctorial crustaceans, the general pattern seems →OMIT thus to →have become partially obscured.

There is another and equally curious branch of

the present

our present

our

subject; namely, →serial homologies, or the comparison of the

same

different

part

parts

→or organs in the same individual, and not of the

different

same

parts or organs in →different members of the same class. Most physiologists believe that the bones of the skull are

homologous with—

homologous—

that

is,

correspond in number and in relative

connexion with—

connexion—

the

with the

elemental parts of a certain number of vertebræ. The anterior and posterior limbs in →all the higher vertebrate classes are plainly homologous. →So it is with the wonderfully complex jaws and legs

crustaceans. It is familiar to almost every one, that in a flower the relative position of the sepals, petals, stamens, and pistils, as well as their intimate structure, are intelligible on the view that they consist of metamorphosed leaves, arranged in a spire. In monstrous plants, we often get direct evidence of the possibility of one organ being transformed into another; and we can actually

see

see,

→during the early or embryonic stages of development in flowers, →as well as in crustaceans and many other animals, that organs, which when mature become extremely

different,

different

are at →first exactly alike.

How inexplicable are →the cases of serial homologies on the ordinary view of creation! Why should the brain be enclosed in a box composed of such numerous and such

extraordinary

extra-ordinarily

extraor- dinarily

extraordinarily

shaped pieces of →bone, apparently representing vertebræ? As Owen has remarked, the benefit derived from the yielding of the separate pieces in the act of parturition

mammals, will by no means explain the same construction in the skulls of →birds and reptiles. Why should similar bones have been created →to form the wing and

leg

the leg

of a bat, used as they are for such totally different →purposes, namely flying and walking? Why should one crustacean, which has an extremely complex mouth formed of many parts, consequently always have fewer legs; or conversely, those with many legs have simpler mouths? Why should the sepals, petals, stamens, and

pistils

pistils,

any individual

each

flower, though fitted for such

widely different

distinct

purposes, be all constructed on the same pattern?

On the theory of natural selection, we

can

can,

→to a certain extent, answer these questions. →We need not here consider how the bodies of some animals first became divided into a series of →segments, or how they became divided into →right and left sides, with corresponding organs, for such questions are almost beyond investigation. It is, however, probable that some serial structures are the result of cells multiplying by division, entailing the multi-