Origin of Species Variorum

Comparison with 1869

pistils are essentially alike in nature. An animal may possess various parts in a perfect state, and yet they may in one sense be rudimentary, for they are useless: thus the tadpole of the common Salamander or newt, as Mr. G. H. Lewes remarks, "has gills, and passes its existence "in the water; but the Salamandra atra, which lives "high up among the mountains, brings forth its young "full-formed. This animal never lives in the water. "Yet if we open a gravid female, we find tadpoles "inside her with exquisitely feathered gills; and when "placed in water they swim about like the tadpoles of the "water-newt. Obviously this aquatic organisation has "no reference to the future life of the animal, nor has "it any adaptation to its embryonic condition; it has "solely reference to ancestral adaptations, it repeats a "phase in the development of its progenitors."

An organ, serving for two purposes, may become rudimentary or utterly aborted for one, even the more important purpose; and remain perfectly efficient for 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 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

pistil are. .. .. .. .. ↑

An organ serving for two purposes, may become rudimentary or utterly aborted for one, even the more important purpose, and remain perfectly efficient for 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 its 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 and conjoined 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. ↑ As they would be of still less use, when in a still less developed condition, they cannot under the present state of things have been formed by natural selection, which .. acts solely by the preservation of useful modifications. 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 in a nascent condition; looking to the past, creatures with an organ in a nascent