Chap. XIV.] AND ABORTED ORGANS. 257 



important purpose, and remain perfectly efl&cient for 

 the other. Thus in plants, the office of the pistil is t,o 

 allow the pollen-tubes to reach the ovules within the 

 ovarium. The pistil consists of a stigma supported on 

 a style; but in some Compositae, 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 in the usual man- 

 ner with hairs, which serve to brush the pollen out of 

 the surrounding and conjoined anthers. Again, an or- 

 gan may become rudimentary for its proper purpose, 

 and be used for a distinct one: in certain fishes the 

 swim-bladder seems to be rudimentary for its proper 

 function of giving buoyancy, but has become converted 

 into a nascent breathing organ or lung. Many similar 

 instances could be given. 



Useful organs, however little they may be developed, 

 unless we have reason to suppose that they were for- 

 merly more highly developed, ought not to be consid- 

 ered as rudimentary. They may be in a nascent condi- 

 tion, and in progress towards further development. 

 Eudimentary organs, on the other hand, are either quite 

 useless, such as teeth which never cut through the gums, 

 or almost useless, such as the wings of an ostrich, which 

 serve merely as sails. As organs in this condition would 

 formerly, when still less developed, have been of even 

 less use than at present, they cannot formerly have been 

 produced through variation and natural selection, which 

 acts solely by the preservation of useful modifications. 

 They have been partially retained by the power of in- 

 heritance, and relate to a former state of things. It is, 

 however, often difficult to distinguish between rudimen- 

 tary and nascent organs; for we can judge only by analogy 



