570 Professor E. B. Poulton on Mr. Thayer's 



XXVII. A brief discussion of A. H. Thayer's suggestions as 

 to the meaning of colour and pattern in insect 

 Uonomics. By Professor Edward B. Poulton, 

 M.A., D.Sc, F.R.S, etc. 



[Read October 21.st, 1903.] 



The discoverer of the meaning of the white iinder-sides of 

 animals is entitled to a resjDectful hearing on any question 

 of animal coloration. Furthermore, by his discovery, he 

 has proved the benefits which the artist can confer on the 

 naturalist, benefits which we naturalists are only too 

 pleased to receive with gratitude. Our only difficulty is 

 that so few artists seem disposed to consider our problems 

 seriously. In order to be able to do so they must become, 

 at least in spirit, naturalists as well as artists. The more 

 numerous the men of creative power who can occupy, as 

 Mr. Thayer does, the double standpoint, the better it will 

 be for both domains. I therefore express my cordial 

 agreement with Mr. Thayer's claim for the artist. I now 

 propose to make a few comments upon the details of his 

 interesting paper. 



Every naturalist will agree that " any coloration or 

 pattern would be conspicuous somewhere." We have often 

 called attention to the fact that colour, pattern, shape, 

 and attitude can only be understood in the natural environ- 

 ment. In fact, Mr. Thayer's own suggestions are, I think, 

 most open to criticism when he is speaking of animals in 

 countries he has not visited ; when, for instance, he sug- 

 gests the kind of concealment brought about by the stripes 

 of the zebra. The lion is the zebra's great enemy, and in 

 spite of their very different kind of colouring they are both 

 adapted to the same general environment. The propor- 

 tion of dark and light stripes, Francis Galton told us long 

 ago, "is such as exactly to match the pale tint which arid 

 ground possesses when seen by moonlight." So too the 

 suggestion that the groups of similar South American 

 butterflies have gained their resemblance by a common 

 (syncryptic) likeness to some flower which they chiefly 

 frequent would be more plausible if Mr. Thayer had 

 studied them in their native haunts. I have asked Mr, 



