314 SPARKS FROM A GEOLOGIST^ HAMMER. 



raised the question of the significance of " rudimental 

 organs." Now, the rudiments of a " row-lock " upon a 

 sail-rigged vessel would be entirely inexplicable; but the 

 rudiments of eyes in the blind fish of the Mammoth Cave 

 become explicable, because we know they might be the 

 effete remnants of functional eyes in some remote pro- 

 genitor. Rudimental organs, then, it must be admitted, 

 add a separate probability to the theory that equine re- 

 lationships are relationships of consanguinity. The horse- 

 series itself offers in its "splint bones" and other struct- 

 ures admirable examples of rudimental organs. 



In this connection, it only remains to direct the reader's 

 attention to the fact that the original article not only 

 does not deny the probability of a genealogical descent 

 along the equine succession of past times, but it does not 

 deny the efficiency of the Darwinian principle of '' natural 

 selection." It implies that this is not an adequate and 

 all-sufficient principle. Nor does it imply, in offering a 

 parallel between a series of structures resulting from 

 human contrivance, and a series of structures appearing 

 in the natural world, that therefore the true and only 

 conception of " designs " in nature is typified by the lim- 

 ited, groping contrivances of man. This was charged in 

 the reply signed by " Pikestaff.'' In fact, the point of 

 my satire did not depend on any assumption concerning 

 designs in nature. If, however, it were needed to offer 

 a reply to the Pikestaffian objection, for it possesses a 

 generic character, I should point simply to the line of 

 thought set forth in the last article of this volume. The 

 Pikestaffian objection has become quite threadbare. I 

 think the owners would do well to throw it now upon 

 the pile of old rags. 



