Origin of Species Variorum

→ if we admit 1869 1872

on the view of 1859 1860 1861 1866

→ OMIT 1869 1872

which are considered by naturalists as allied, 1859 1860 1861 1866

→ natural 1859 1860 1861 1866 1869

variation and natural 1872

→ dimorphic forms, and 1869 1872

and 1859 1860 1861

dimorphic states, and 1866

→ be 1859 1860 1861 1866 1869

differ from each other 1872

→ different species 1869 1872

homologous organs, to whatever purpose applied, 1859 1860 1861 1866

→ same class in their homologous organs, to whatever purpose applied; 1869 1872

different species of a class; 1859 1860 1861

different species in the same class; 1866

→ homologous parts 1869

homologous parts constructed on the same pattern 1859 1860 1861 1866

serial and lateral homologies 1872

→ close resemblance in the 1869 1872

resemblance in an 1859 1860 1861 1866

→ parts which are homologous, and which 1869 1872

homologous parts, which 1859 1860 1861 1866

→ OMIT 1869 1872

from each other 1859 1860 1861 1866

→ in allied though very distinct species of their 1869

in different species of a class of the 1859 1860 1861

in different species of the same class of the 1866

of the 1872

→ though 1859 1860 1861 1866 1869

in allied though distinct species, though 1872

→ a greater or less degree in relation 1869 1872

relation 1859 1860 1861 1866

→ with their modifications 1869 1872

through the principle of modifications being 1859 1860 1861 1866

→ a corresponding 1869

corresponding 1859 1860 1861 1866

a corresponding early 1872

such rules;— all naturally follow →if we admit the common parentage of

those

allied

forms

forms,

→OMIT together with their modification through →natural selection, with

the

its

contingencies of extinction and divergence of character. In considering this view of classification, it should be borne in mind that the element of descent has been universally used in ranking together the sexes, ages, →dimorphic forms, and acknowledged varieties of the same species, however

much

different

they may →be in structure. If we extend the use of this element of descent,— the

only

one

certainly known cause of similarity in organic beings,— we shall understand what is meant by the

natural

Natural

system:

System:

it is genealogical in its attempted arrangement,

and

with

the grades of acquired difference

are marked

marked

by the

terms

terms,

varieties, species, genera, families, orders, and classes.

On this same view of descent with modification,

most of

all

the great facts in Morphology become intelligible,— whether we look to the same pattern displayed

the →different species of the →same class in their homologous organs, to whatever purpose applied; or to the →homologous parts in each individual animal and plant.

On the principle of successive slight variations, not necessarily or generally supervening at a very early period of life, and being inherited at a corresponding period, we can understand the

~~great~~

great

leading facts in Embryology; namely, the →close resemblance in the individual embryo of the →parts which are homologous, and which when matured

will

....

become widely different →OMIT in structure and function; and the resemblance →in allied though very distinct species of their homologous parts or

organs

organs,

→though fitted in the adult

members

state

for