XXVI. Protective Coloration in its relation to Mimiery, 
Common Warning Colours, and Sexual Selection. 
By Assorr H. THAYER. Communicated by 
Pror. Epwarp B. Poutton, M.A., D.Sc., F.R.S. 
[Read October 21st, 1903. ] 
Tue 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 Corvide, for 
instance,—and equally plain that there must be Mimicry, 
both Batesian and Miillerian. 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.) 
