SPECIAL PROCRYPSIS 197 



concealed by the hind wing was of a more usual dull 

 grey-brown colour. The moth when disturbed flew away 

 to another similar tuft of grass and adopted the same 

 attitude again, which was most certainly procryptic, and 

 very unusual in a moth of this group, the members of which 

 usually rest with the wings brought closely against the 

 body. The fact that the silver grey colour was confined 

 to those parts of the wings where it was necessary for the 

 concealment of the moth by procrypsis is a very important 

 point. Many other examples of this nature exist, and are 

 arguments against such protective colouration being the 

 result of mere chance. Natural selection produces no 

 more than is necessary : this is contrary to the doctrine 

 of Hypertely. Exactly similar limitations are to be met 

 with when studying mimicry. ^ 



Another beautiful instance of special procrypsis is 

 afforded by a rare Notodontid moth,^ of which I found 

 a specimen at rest on a bush on Damba Isle. The only 

 specimen known up till then was the type in the British 

 Museum. 



This moth so closely resembled the tube formed by a 

 dead,, dry, rolled-up leaf, that I was for long in doubt 

 as to its nature, and finally had to pluck the twig on 

 which it sat and examine the object most minutely before 

 I could decide. 



The wings were closely folded round the body ; the 

 inner margins of the fore wings meeting over the back 

 were of slightly darker tint than the rest of tjie wing, 

 so as to resemble the thick midrib of a dried leaf, whose 

 petiole was represented by a curved tuft of long hairs 

 projecting upwards from the top of the head. 



The colour of the wings was the shining brown of a 

 crisp, dry leaf, and on each side there were several lines 

 representing venules, and three doubly ringed markings 



* Essays on Evolution, Poulton, p. 240. 

 ^ Scalmicauda niveiplaga. 



