Origin of Species Variorum

→ in classifying varieties, as with 1859 1860 1861 1866

as in classifying 1869 1872

→ sub-varieties differ from the others 1859 1860 1861 1866

of the sub-varieties differ 1869 1872

→ having a longer 1859 1860 1861 1866 1869

the length of the 1872

→ reasoning or thinking 1859 1860 1861 1866

thought 1869 1872

namely, closeness of descent with various degrees of modification. Nearly the same rules are followed →in classifying varieties, as with species. Authors have insisted on the necessity of

arranging

classing

varieties on a natural instead of an artificial system; we are cautioned, for instance, not to class two varieties of the pine-apple together, merely because their fruit, though the most important part, happens to be nearly identical; no one puts the

swedish

Swedish

and common

turnip

turnips

together, though the esculent and thickened stems are so similar. Whatever part is found to be most constant, is used in classing varieties: thus the great agriculturist Marshall says the horns are very useful for this purpose with cattle, because they are less variable than the shape or colour of the body, &c.; whereas with sheep the horns are much less serviceable, because less constant. In classing

varieties;

varieties,

I apprehend

that if

we had a real pedigree, a genealogical classification would be universally

preferred:

preferred;

and it has been attempted

some

cases.

authors.

For we might feel sure, whether there had been more or less modification,

that the

the

principle of inheritance would keep the forms together which were allied in the greatest number of points. In tumbler pigeons, though some →sub-varieties differ from the others in the important character of →having a longer beak, yet all are kept together from having the common habit of tumbling; but the short-faced breed has nearly or quite lost this

habit:

habit;

nevertheless, without any →reasoning or thinking on the subject, these tumblers are kept in the same group, because allied in blood and alike in some other respects. If it could be proved that the Hottentot had descended from the Negro, I think he would be classed under the Negro group, however much he might differ in colour and other important characters from negroes.