40G KUDIMENTAHV, ATROPHIED, Chat. XIII. 



adaptation to its cniljrvonic condition ; it has solely reference 

 to ancestral adaptations, it repeats a phase in the development 

 of its profi^enitors." 



An ornj-an, serving; for two purposes, may become rudimen- 

 tary or utterly aborted for one, even the more important pur- 

 pose, and remain perfectly eflicient for the other. Thus in 

 plants, the oflice 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 Composita?, the 

 male florets, which of course cannot bo fecundated, have a ru- 

 dimentary pistil, for it is not crowned with a stigma ; but the 

 stylo remains Avell developed, and is clothed with hairs, in the 

 usual manner, for brushing the pollen out of the suiTOunding 

 and conjoined anthers. Again, an organ may become rudi- 

 mentary for its proper purpose, and be used for a distinct ob- 

 ject : in certain fish the swim-bladder seems to be nearly rudi- 

 mentary for its proper function of giving buoj-ancy, 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 rudiincntarv : they may be called nascent, 

 and may hereafter be developed by natural selection to any 

 further extent. Kudimentary oigans, on the other hand, are 

 essentially useless, as teeth which never cut through the gums. 

 As they would be of even less use, Avhen in a still less devel- 

 oped condition, they cannot have been formed through varia- 

 tion and natm-al selection, which latter acts solely by the pres- 

 ervation of useful modilications. They relate to a former 

 state of things, and have been partially retained by the power 

 of inheritance. It is difficult to know what organs are nas- 

 cent ; 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 this 

 condition will generally have been supplanted by their suc- 

 cessors with the same organ in a more perfect state, and con- 

 sequently will have become long ago extinct. The wing of 

 the penguin is of high service, acting as a fin ; it may, there- 

 fore, represent the nascent state of the Aving ; not that I be- 

 li(>ve this to be the case ; it is more probably a reduced organ, 

 modilied for a new function: the wing of the Apteryx, on the 

 otiier hand, is c[uite useless, and is ti-uly rudimentary. Tlic 

 simple lilamentary limbs of the Lepidosiren ajiparently are in 

 a nascent state; for, as Owen lias remarked, th(>v are the 



