[Darwinism (1889) by Alfred Russel Wallace]@TWC D-Link bookDarwinism (1889) CHAPTER III 39/51
We have here an example of the same amount of "independent variability" that, as we have seen, occurs in the various dimensions of birds and mammals; and it may be taken as an illustration of the kind and degree of variability that may be expected to occur among small and little specialised flowers.[29] In the common wind-flower (Anemone nemorosa) an almost equal amount of variation occurs; and I have myself gathered in one locality flowers varying from 7/8 inch to 1-3/4 inch in diameter; the bracts varying from 1-1/2 inch to 4 inches across; and the petaloid sepals either broad or narrow, and varying in number from five to ten.
Though generally pure white on their upper surface, some specimens are a full pink, while others have a decided bluish tinge. Mr.Darwin states that he carefully examined a large number of plants of Geranium phaeum and G.pyrenaicum (not perhaps truly British but frequently found wild), which had escaped from cultivation, and had spread by seed in an open plantation; and he declares that "the seedlings varied in almost every single character, both in their flowers and foliage, to a degree which I have never seen exceeded; yet they could not have been exposed to any great change of their conditions."[30] The following examples of variation in important parts of plants were collected by Mr.Darwin and have been copied from his unpublished MSS.:-- "De Candolle (_Mem.Soc.Phys.de Geneve_, tom.ii.part ii.p.
217) states that Papaver bracteatum and P.orientale present indifferently two sepals and four petals, or three sepals and six petals, which is sufficiently rare with other species of the genus." "In the Primulacae and in the great class to which this family belongs the unilocular ovarium is free, but M.Dubury (_Mem.Soc.Phys.
de Geneve_, tom.ii.p.
406) has often found individuals in Cyclamen hederaefolium, in which the base of the ovary was connected for a third part of its length with the inferior part of the calyx." "M.
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