Origin of Species Variorum

Comparison with 1869

the other. Thus in plants, the office of the pistil is to allow the pollen-tubes to reach the ovules within the ovarium. .. .. .. The pistil consists of a stigma supported on a style; but in some Compositæ, the male florets, which of course cannot be fecundated, have a rudimentary pistil, for it is not crowned with a stigma; but the style remains well developed, and is clothed with hairs, in the usual manner, for brushing the pollen out of the surrounding and conjoined anthers. Again, an organ may become rudimentary for its proper purpose, and be used for a distinct object: in certain fish the swimbladder seems to be rudimentary for its proper function of giving buoyancy, but has become converted into a nascent breathing organ or lung. Other similar instances could be given.

Organs, however little developed, if of use, should not be considered as rudimentary: they may be called nascent, and may hereafter be developed to any extent by natural selection. Rudimentary organs in the individuals of the same species are very liable to vary in degree of development and in other respects. ↑ As they would be of even less use, when in a still less developed condition, they cannot have been formed through variation and natural selection, which latter acts solely by the preservation of useful modifications. They relate to a former state of things, and have been partially retained by the power of inheritance. It is difficult to know what are nascent organs; looking to the future, we can- not of course tell how any part will be developed, and whether it is now in a nascent condition; looking to the past, creatures with an organ in this condition will generally have been supplanted .. by their successors with the same organ in a more perfect state, and consequently will have become long ago extinct. The wing of the penguin is of high service, acting as a fin;

the other. Thus in plants, the office of the pistil is to allow the pollen-tubes to reach the ovules protected in the ovarium at its base. The pistil consists of a stigma supported on the style; but in some compositæ, the male florets, which of course cannot be fecundated, have a pistil, which is in a rudimentary state, for it is not crowned with a stigma; but the style remains well developed, and is clothed with hairs as in other compositæ, for the purpose of brushing the pollen out of the surrounding anthers. Again, an organ may become rudimentary for its proper purpose, and be used for a distinct object: in certain fish the swim-bladder seems to be nearly rudimentary for its proper function of giving buoyancy, but has become converted into a nascent breathing organ or lung. Other similar instances could be given.

Organs, however little developed, if of use, should not be called rudimentary: they may be called nascent, and may hereafter be developed by natural selection to any further extent. Rudimentary organs, on the other hand, are essentially useless, as teeth which never cut through the gums. Moreover, in closely allied species, the degree to which the same organ has been rendered rudimentary occasionally differs much. ↑ They relate to a former condition of their possessor, and have been retained, as we shall see, by inheritance. .. .. .. .. .. .. .. .. It is difficult to know what organs are nascent; looking to the future, we cannot of course tell how any part will be developed, and whether it is now nascent; looking to the past, creatures with an organ in a nascent condition will generally have been supplanted and exterminated by their successors with the organ in a more perfect and developed condition. The wing of the penguin is of high service, and acts as a fin;