HEMIPTERA. 



197 



b. Tarsi 2-jointed. 



* Membrane with longitu- 

 dinal nervures. 



a. Ventral spine short, not 

 passing the intermediate 

 coxae. 



** Second joint of the 

 antennae distinctly 

 longer than the third; 

 body broadly ovate. .31. ANISCHYS. 

 ft Second and third 

 joints of the antennae 

 about equal ; body 



elongate 32. RHOPALIMORPHA. 



jS. Ventral spine long, 

 reaching or passing the 

 anterior coxae. 

 ** Lateral angles of the 



thorax spinous .... 33. DUADICUS. 

 ft Lateral angles of the 



thorax unarmed .... 34. STAURALIA. 

 t Membrane with reticu- 

 lated nervures 43. BEB^EUS. 



b. Sternum more or less distinctly 

 keeled. 

 1. Tarsi 3-jointed. 



a . Sternum with a single central 

 keel. 



* Central lobe of the head 

 as long or longer than the 

 lateral lobes. 



a. Lateral angles of the 

 thorax unarmed or sim- 

 ply spinous 36. CUSPICONA. 



j3. Lateral angles of the 



thorax cornuted 40. TAUROCERUS. 



t Lateral lobes of the head 



longer than the central lobe. 



a. Sternal keel small; mar- 

 gins of the abdomen un- 

 armed ; posterior mar- 

 gin of the thorax not 

 produced 39. ARVELIUS. 



j8 . Sternal keel very large ; 

 margins of the abdomen 

 spinose ; posterior mar- 



