NEPINA, 47 



segments after the same type as Nepidce, but the last segment is posteriorly 

 obtuse. Gen. 1, Ranatra. 



FAMILY 2. NEPIDJ2. 



Long-oval, flat, thin. Antennae : second joint produced laterally 

 at the end into a long falcate process ; third nearly as long as, and 

 incumbent on, the second. Eyes moderate, reniform, prominent. 

 Rostrum almost vertical, conical. Pronotum broad-trapeziform : 

 the first two thirds with longitudinal callosities, the last third flat, 

 incrassated at the sides ; posterior margin slightly concave. Scu- 

 tellum large, triangular. Elytra flat, as long as the abdomen, reti- 

 culated throughout ; Embolium long, parallel, indistinct on the upper 

 side ; Membrane indistinctly separated from the Corium. Sternum : 

 Prosternum posteriorly retuse, xyphus rounded ; Meso- and Meta- 

 sternum transverse. Legs : first pair ; coxce stout, not half the 

 length of the thighs ; thighs incrassated, suddenly smaller towards 

 the apex ; the groove wide ; tibiae curved ; tarsi digitate : second 

 and third pairs longest, simple ; C^XCB subglobose ; tarsi long and 

 slender; claws thin. 



Abdomen beneath, with a depressed middle keel ; the first and second 

 segments anchylosed, so that there appear to be but five abdominal seg- 

 ments ; the posterior margin of each concave above, angularly excised 

 beneath, except the last. Genital segments in $ and $ outwardly of the 

 same form. Above, in the middle of the last abdominal segment, lies a 

 small, triangular, pointed plate, which (according to Elor) is the only 

 visible part of the third genital segment, the rest of its development being 

 under the second segment for nearly its whole length ; the second seg- 

 ment, large, subtriangular, cleft up the middle, but not parted, projects 

 far beyond the points of the last abdominal segment, and forms the apex 

 of the abdomen, a spinose point lying on each side of the terminal fila- 

 ments ; beneath, this segment appears as two long, narrow, triangular 

 lateral plates, grooved on their inner margins, the space between them 

 filled by a long, triangular, convex plate, whose side margins fit into the 

 groove of the side plates ; the first segment and the generative organs 

 are covered by the second segment. Gen. 1, Nepa. 



