Insect Colouring 



to our retorts. For the moment, I shall 

 perhaps be contributing a grain of sand to 

 the future palace if I describe the little that 

 I have seen. 



My basic observation dates a long way 

 back. I was at that time busy with the 

 Hunting Wasps, following their larval de- 

 velopment from the egg to the cocoon. Let 

 us take an instance from my notes, which 

 cover nearly all the game-hunters of my 

 district. I will choose the larva of the Yel- 

 low-winged Sphex, 1 which, with its convenient 

 size, will furnish an easy object-lesson. 



Under the transparent skin of the larva, 

 which has been recently hatched and is con- 

 suming: its first Cricket, we soon perceive 

 some fine white spots, which rapidly increase 

 in size and number and eventually cover the 

 whole body, except the first two or three seg- 

 ments. On dissecting the grub, we find that 

 these spots have to do with the adipose layer, 

 of which they form a considerable part, for, 

 far from being scattered only on the surface, 

 they run through its whole thickness and are 

 present in such numbers that the forceps can- 

 not seize the least fragment of this tissue 

 without picking up a few of them. 



1 Cf . The Hunting Wasps: chap. iv. — Translator's 

 Note. 



275 



