260 SEDIMENTARY, ATROPHIED, [Chap. XW 



or in order " to complete the scheme of nature." But 

 this is not an explanation, merely a re-statement of the 

 fact. Xor is it consistent with itself: thus the boa- 

 constrictor has rudiments of hind-limbs and of a pelvis, 

 and if it be said that these bones have been retained 

 " to complete the scheme of nature," why, as Professor 

 Weismann asks, have they not been retained by other 

 snakes, which do not possess even a vestige of these 

 same bones ? What would be thought of an astronomer 

 who maintained that the satellites revolve in elliptic 

 courses round their planets " for the sake of symmetry," 

 because the planets thus revolve round the sun ? An 

 eminent physiologist accounts for the presence of rudi- 

 mentary organs, by supposing that they serve to excrete 

 matter in excess, or matter injurious to the system ; but 

 can we suppose that the minute papilla, which often 

 represents the pistil in male flowers, and which is 

 formed of mere cellular tissue, can thus act ? Can we 

 suppose that rudimentary teeth, which are subsequently 

 absorbed, are beneficial to the rapidly growing embryonic 

 calf by removing matter so precious as phosphate of 

 lime ? When a man's fingers have been amputated, 

 imperfect nails have been known to appear on the 

 stumps, and I could as soon believe that these vestiges 

 of nails are developed in order to excrete horny matter, 

 as that the rudimentary nails on the fin of the manatee 

 have been developed for this same purpose. 



On the view of descent with modification, the origin 

 of rudimentary organs is comparatively simple ; and we 

 can understand to a large extent the laws governing 

 their imperfect development. We have plenty of cases 

 of rudimentary organs in our domestic productions, — as 

 the stump of a tail in tailless breeds, — the vestige of an 



