RIVER GARDENS ; 



his voracity makes him the terror of every other 

 class of aquatic insect life. "Woe to the Boat Beetle, 

 or Nepa, coming within range of his dinner excur- 

 sion he is seized, and literally torn to pieces in an 

 instant by this destructive creature. His change to 

 the perfect, or beetle state, takes place in a structure 

 which he forms at the necessary period, somewhat 

 analogous to the chrysalis, or pupa case in which 

 the caterpillar is gradually transformed into the 

 butterfly. 



This case contains the semi-torpid form, which 

 developing itself into the perfect Dyticus, generally 

 lies buried in the mud at the bottom of streams or 

 ponds, or in the adjacent banks, in a secure spot 

 selected by the larva, where he burrows to undergo 

 his change in safety. Prom this receptacle the per- 

 fect Dyticus emerges in due time. He is a handsome 

 swimming Beetle (Plate III., No. 2) ; but though 

 improved in personal appearance, his habits have not 

 amended he is as voracious as in his larva stage. 

 Small fish, even the Stickleback, in his plate armour, 

 often become his victim, and the number of tad- 

 poles he will consume at a long drawn-out meal, 

 extending over great part of the fore and after-noon, 

 is something extraordinary. A pair of these Beetles 

 should not therefore be placed in an Aquarium, ex- 



