210 GEOEGE JOHN EOMANBS issi- 



1st. Even assuming, for sake of argument, that 

 heightened colour is correlated with increased vigour, 

 Wallace everywhere fails to distinguish between bril- 

 liancy and ornament ; yet it is the disposition of colours 

 in patterns, &c., that is the chief thing to be explained. 



2nd. In many cases {e.g. peacock's tail) the pattern 

 is only revealed when unfolded during courtship. 

 Besides natural selection could not be such a fool as to 

 develope large (physiologically expressive) and weighty 

 (impeding flight) structures like this — stags' antlers, 

 &c., merely as correlates of vigour. 



3rd. There is not much in Wallace's merely 

 negative difficulty about our not knowing what goes 

 on in the mind of a hen, when we set against that 

 difficulty the positive fact that we can see what does 

 go on in the mind of a cock — display, antics, song, &c. 



4th. To say that ' each bird finds a mate under any 

 circumstances ' is merely to beg the whole question. 



6th. There remains Wallace's jealousy of natural 

 selection. He wUl not have any other ' factor,' and 

 therefore says natural selection must eat up sexual 

 selection like the lean kine have the fat kine. But 

 natural selection alone does not explain all the 

 phenomena of sexual colouring, courtship, &c., and 

 sexual selection is exactly the theory that does. 

 Wallace's jealousy, therefore, is foolish and inimical 

 to natural selection theory itself, by forcing it into 

 explanations which are plainly false. 



My own behef is, that what Lankester calls the 

 ' pure Darwinians ' are doing the same thing in 

 another direction. By endeavouring, with Wallace 

 and Weismann, to make natural selection all in all as 



