DESCENT OF MAN FROM SOME LOWER FORM. 147 



in rendering a useless part rudimentary. But this prin- 

 ciple will almost necessarily be confined to the earlier 

 stages of the process of reduction ; for we can not sup- 

 pose that a minute papilla, for instance, representing in 

 a male flower the pistil of the female flower, and formed 

 merely of cellular tissue, could be further reduced or 

 absorbed for the sake of economizing nutriment. 



Finally, as rudimentary organs, by whatever steps 

 they may hare been degraded into their present useless 

 condition, are the record of a former state of things, and 

 have been retained solely through the power of inherit- 

 ance, we can understand, on the genealogical view of 

 classification, how it is that systematists, in placing or- 

 ganisms in their proper places in the natural system, 

 have often found rudimentary parts as useful as, or even 

 sometimes more useful than, parts of high physiological 

 importance. Eudimentary organs may be compared with 

 the letters in a word, still retained in the spelling, but 

 become useless in the pronunciation, but which serve as 

 a clew for its derivation. On the view of descent with 

 modification, we may conclude that the existence of organs 

 in a rudimentary, imperfect, and useless condition, or 

 quite aborted, far from presenting a strange difficulty, as 

 they assuredly do on the old doctrine of creation, might 

 even have been anticipated in accordance with the views 

 here explained. 



main's deficiency in tail. 



Descent According to a popular impression, the ab- 



of Man, sence of a tail is eminently distinctive of man ; 

 but, as those apes which come nearest to him 

 are destitute of this organ, its disappearance does not 

 relate exclusively to man. The tail often differs remark- 



