44 naucorina. 



Family L— APHELOCHIRID^. 



Oval, depressed. Antennce : the four joints progressively longer. 

 Rostrum reaching to the second abdominal segment, resting on the 

 sternum; second joint very long. P/'o«o^f^M?^ subtrapezoidal ; anterior 

 margin very roundly concave, anterior angles produced exterior to 

 the eyes, hinder angles projecting. Elytra (rarely developed) in 

 repose leaving a broad lateral portion of the abdomen uncovered ; 

 Membrane nerveless, Sternimi : Prosternmn concave at the sides ; 

 Mesosternum short, with a middle keel ; Metasteruum depressed, tri- 

 angular, sides raised. Legs : thighs, third pair longest, simple ; 

 tibi(E, third pair compressed, subtrigonate, ciliated ; tarsi, first 

 and second pairs stoutest, about one third the length of the tibiae ; 

 third pair slender, rather shorter than the tibiae ; chnvs long, slender. 



Abdomen beneath ; the posterior margin of the segments except the last 

 angularly cut out, the last roundly for the reception of the wide genital 

 segments, which project a little beyond the acute points ; the posterior 

 margin, in the middle, with two small points. Gen. 1, Aphelocheirus. 



Section I.—NATJCOBINA. 



Nepidse, p., Leach; Westw. 

 Nepini, p., Biirm. 

 Naucorides, Am. et Serv. 

 Naucoridse, Fieb. 

 Naucoridea, Flor. 



Head short, transverse; Face very short, vertical. Antennce 

 4-jointed, stout, simple ; inserted on the under side of the head, and 

 lying in a cavity beneath each eye. Eyes posterior, very large, tri- 

 angular. Rostrum 3-jointed, free, short, thick, conical, nearly ver- 

 tical; Lahriim large, triangular. Pronotum transverse, subtrape- 

 zoidal, wider than the head. Scutellicm large, triangular. Elytra 

 pergamentous throughout ; Clavus broad ; Emholium broad, dis- 

 tinct, nearly half the length of the corium ; Membrane indistinctly 

 separated from the corium,* nerveless. Winys laid in two longitu- 



* The distinction clearly seen on the under side. 



