200 



HENRY LA.URENS 



1(^ 



2 4 6 



Photographs at about 1| magnification of living animals, not anaesthetized, 

 taken by Prof. Alexander Petrunkevitch, to whom it is a pleasure to express 

 here my thanks. Figures 3 and 4 are unfortunately slightly out of focus. Larvae 

 that have been in darkness for several hours when brought into the light are 

 rather restive, and it is some little time before they can be quieted sufficiently 



