WATER BEETIoES IN RELATION TO PONDFISH CULTURE. 



303 



Fig. 84.— Dorsal view of larva of Dineutes americanus. Fig. 85.— Head of same, enlarged. Fig. 86.— Antenna. Fig. 87. — Man- 

 dible. Fig. 88.— Maxilla, dorsal view. Fig. 89.— Labium, ventral view. Figs. 90 and 91.— External and internal hook on 

 last segment of abdomen. 



