Comparison with 1859 |
|
breeds of pigeons,
in countries most
widely apart, present sub-varieties with reversed feathers on the head
and feathers
on the
feet,— feet,— 1859 1860 1861 1872 | feet, — 1866 1869 |
characters not possessed by the aboriginal rock-pigeon; these then are analogous variations in two or more distinct races. The frequent presence of fourteen or even sixteen tail-feathers in the
pouter, pouter, 1859 1860 1861 | pouter 1866 1869 1872 |
may be considered as a variation representing the normal structure of another race, the fantail. I presume that no one will doubt that all such analogous variations are due to the several races of the pigeon having inherited from a common parent the same constitution and tendency to variation, when acted on by similar unknown influences. In the vegetable kingdom we have a case of analogous variation, in the enlarged stems, or roots as commonly called,
of the Swedish turnip and Ruta baga, plants which several botanists rank as varieties produced by cultivation from a common parent: if this be not so, the case will then be one of analogous variation in two so-called distinct species; and to these a third may be added, namely, the common turnip. According to the ordinary view of each species having been independently created, we should have to attribute this similarity in the enlarged stems of these three plants, not to the
vera
causa
of community of descent, and a consequent tendency to vary in a like manner, but to three separate yet closely related acts of creation. ↑2 blocks not present in 1859 1860 1861; present in 1866 1869 1872 | Many similar cases of analogous variation have been observed by Naudin in the great gourd-family, and by various authors in our cereals.
Similar cases occurring with insects under their
natural conditions have lately been discussed with much ability by Mr. Walsh, who has grouped them under his law of Equable Variability.
|
|
|
With pigeons, however, we have another case, namely, the occasional appearance in all the breeds, of slaty-blue birds with two black bars on the wings, a
white
|
breeds of
pigeons, pigeons, 1859 1860 1861 1866 1869 | the pigeon, 1872 |
in countries
most most 1859 1860 1861 1866 1869 | most 1872 |
widely apart, present sub-varieties with reversed feathers on the
head head 1859 1860 1861 1866 1869 | head, 1872 |
and
feathers feathers 1859 1860 1861 1866 1869 | with feathers 1872 |
on the
feet, — feet, — 1866 1869 | feet,— 1859 1860 1861 1872 |
characters not possessed by the aboriginal rock-pigeon; these then are analogous variations in two or more distinct races. The frequent presence of fourteen or even sixteen tail-feathers in the
pouter pouter 1866 1869 1872 | pouter, 1859 1860 1861 |
may be considered as a variation representing the normal structure of another race, the fantail. I presume that no one will doubt that all such analogous variations are due to the several races of the pigeon having inherited from a common parent the same constitution and tendency to variation, when acted on by similar unknown influences. In the vegetable kingdom we have a case of analogous variation, in the enlarged stems, or
roots as commonly called, roots as commonly called, 1859 1860 1861 1866 1869 |
as commonly called roots, 1872 |
of the Swedish turnip and Ruta baga, plants which several botanists rank as varieties produced by cultivation from a common parent: if this be not so, the case will then be one of analogous variation in two so-called distinct species; and to these a third may be added, namely, the common turnip. According to the ordinary view of each species having been independently created, we should have to attribute this similarity in the enlarged stems of these three plants, not to the
vera
causa
of community of descent, and a consequent tendency to vary in a like manner, but to three separate yet closely related acts of creation. Many similar cases of analogous variation have been observed by Naudin in the great gourd-family, and by various authors in our cereals. Similar cases occurring with insects under
their their 1866 1869 | their 1872 |
natural conditions have lately been discussed with much ability by Mr. Walsh, who has grouped them under his law of Equable Variability. |
|
With pigeons, however, we have another case, namely, the occasional appearance in all the breeds, of slaty-blue birds with two black bars on the wings,
a a 1859 1860 1861 1866 | a 1869 1872 |
white
|