Saui 



642 ISIr. E. Saunders' Synopsis of 



11. CRYPTOCERATA. 



I. Scutellum large. 



A. Abdomen terminatiug in two long filaments . . Ne})[d(B. 



B. Abdomen without apical filaments. 



a. Species more or less oval and depressed . . Kancorida;. 



b. Species more or less elongate, very convex Kotonectidce. 

 II. Scutellum very small, generally invisible .. .. Corixidce. 



NEPIDiE. 



a. Body linear, elongate ; filaments almost as long as the 



body . . . . . . . . . . . . . . Ilanatra. 



b. Body elongate, oval ; filaments not half the length of 



the body . . . . . . . . . . . . . . IScpa. 



Kanatra. 



1. linearis, Linn. Fig. Dougl. & Scott, Brit. Hem. 

 pi. XX. fig. 2. 



Elongate, subcylindrical, dull luteous-brown. Thorax 

 slightly constricted near the middle ; base deeply emargi- 

 nate. Elytra about 2^ times as long as the thoi'ax; body 

 red above ; apex terminating in two long filaments. Legs 

 long ; front pair Avith the coxre more than half the length 

 of the femora; tibia3 recm-ved, not half so long as the 

 femora ; tarsi Avithout claws. 



The tibia3 in the other pairs very long, straight; tarsi 

 thin and with long claws. 



Length — body Avithout filaments, 16 — 18 lines. 

 „ body Avith filaments, 30 — 33 lines. 



Not common ; in ponds, Wandsworth, Hammersmith, &c. 



Nepa. 



\. cinerea, Linn. Fig. Dougl. & Scott, Brit. Hem. pi. xx. 

 fig. L 



Luteous-broAvn, flat, Avide. Thorax subtrapezoidal. 

 Elytra with the sides rounded; apex somcAvhat pointed, 

 their surface finely reticulated. Abdomen above red, 

 terminating in two long filaments. Legs mottled; front 

 thighs thick, deeply grooved and excavated beneath at the 

 base. 



Length 8 — 10 lines; Avith filaments, 12 — 14 lines. 



Common in ponds, &c. 



