Correlated Variation 197 



ing capacity survive, and with them may possibly survive 

 the tendency to have warts on the nose ; the wart-char- 

 acter would thus be preserved, although it may not have 

 direct utility. 



Indeed, many writers, as I have already pointed out, 

 have recognized the facts which show hidden physiologi- 

 cal correlations between things as apparently remote from 

 each other as breathing capacity and warts on the nose. 

 Under the operation of natural selection, variations in 

 bony structure have to be correlated with variations in 

 the muscles which are attached to the bones. A newly 

 appearing character, which is as yet quite insignificant as 

 regards utility, — such as the small lumps on the bone 

 which the paleontologists fondle with such pleasure, as 

 showing the first beginning of later developments of horn, 

 or antler, or weapon of defence — such insignificant charac- 

 ters may ?idiVdincQ pari passu with some remote modification, 

 or be incidentally supplemented by some accommodation 

 which is of utility and which thus acts as a screen to the 

 former in the sense which organic selection postulates. 



This principle — that one character may get the advan- 

 tage of the utihty of another and thus owe its perma- 

 nence and development to it — has been recently and 

 forcibly set forth by Professor Ray Lankester,i in a criti- 

 cism of Professor Weldon, although the point was not 

 new to the literature. The additional impHcation which I 

 now note is that this holds not alone under the ordinary 

 action of natural selection, where both the correlated char- 

 acters — the valuable as well as the valueless one — are 



1 Nature, July l6, 1896, containing instances anrl citations from Darwin. 

 Darwin's treatment of the subject is to be found in his Variation in Ani/nals 

 and Plants, Chap. XXV. 



