Proc. EiiL Soc. Loud., 1917. 



Plate E. 



.»^*n 











m 





....'-'.'eSi^*it*#yii 



■^ c. 



//«i7; /V/rt/;/, /'/i^;/^. Half-Tone Eng. Co. Ltd. 



Pupation of DvTiscis marginalis. 



