( 553 ) 



XXVI. Protective Coloration in its relation to Mimicry, 

 Common Warning Colours, and Sexual Selection. 

 By Abbott H. Thayer. Communicated by 

 Prof. Edward B.Poulton,M.A.,D.Sc., F.R.S. 



[Read October 21st, 1903.] 



The following paper records an artist's examination of the 

 principles of butterflies' coloration, and shows how the 

 results tend to restrict the fields heretofore claimed for 

 Mimicry and Common Warning Colours, and to place 

 them on a basis of Concealing Coloration. It contains 

 also several arguments tending to restrict the hypothesis 

 of Sexual Selection. 



It does not attack the obvious fact that every possible 

 form of advantageous adaptation must somewhere exist. 

 It is obvious to its writer that there must be unpalata- 

 bility accompanied by Warning Coloration, — as apparently 

 in the cases of the Hornbills and Wood Hoopoes reported 

 by Mr. Frank Finn, and probably in many Corvidse, for 

 instance, — and equally plain that there must be Mimicry, 

 both Batesian and MuUerian. Yet every case demands 

 special examination, for the reasons that I shall show 

 herein ; and no apparent conspicuousness of coloration 

 is sure to prove such when examined on the principles 

 established in this article. 



First, it seems necessary to establish the artist's claim 

 to be the judge of all matters of visibility, and the effect, 

 upon the mind, of all patterns, designs, and colours. If 

 even the artist is limited in this, his own field, what 

 hope is there for others ? Fullest wisdom on the part of 

 naturalists would make them adjourn all matters of 

 animals' appearance to us artists, just as any wise ruler 

 gathers about him the most highly specialized minds, to 

 widen, through them, his own scope. 



An artist reads design wherever it occurs, just as a 

 composer reads a score, without playing it, or hearing it. 

 He perceives that every juxtaposition of spots, or shapes, 

 or colours, or of dark and light, and of degrees of these, 



TRANS. ENT. SOC. LOND. 1903. — PART IV. (DEC.) 



