368 Professor E. B. Poulton on colowr-relation, ete. 
now large in the 6th stage, a dark brownish-black rather 
than the dead black of the other 4 and those still on the 
black twigs. 
July 12th. Mature and removed. No further change in 
appearance, 
CONCLUSIONS. 
In this case the grey which overspread the black 
ground-colour of 4 larvee must be regarded as an effect of 
the green environment during the 2 2 last stages. The 5th 
larva took longer to develop, and there was a slight 
departure from “the characteristic dead black of the other 
four. 
