69 



Episternum. — The episternum^ a large rhomboidal sclerite, 

 constitutes most of the body-wall between the sternum and 

 the epipleurae. 



Epimeroii. — Separated from the caudal extremity of the 

 episternum by a distinct suture, is the narrow, curving 

 epimeron^ whose expanded mesal extremity presents two, 

 pointed, curving processes, which enclose the coxal cavity 

 laterad and caudad. The meeting of the epimeron and 

 sternum caudad of the coxal cavity technically closes it, or 

 makes it entire ; if these two sclerites do not meet, as is 

 often the case among beetles, and the cavity is bounded 

 caudad simply by membrane, the cavity is said to be open. 

 If there is no caudal tongue projecting between the cavities, 

 they are said to be confluent ; when separated, as in the speci- 

 men in hand, by this tongue, they are technically separate. 



MESOTHORAX. 



Dorsal aspect. — When the wing-covers are folded the 

 only part of the mesonotum visible is the small, median, tri- 

 angular or shield - shaped portion of the scutellum. By 

 spreading apart or breaking away the wing-covers, the lat- 

 eral membranous portions of the scutellum may be seen, as 

 well as the scutum j the median part of the scutum is 

 strongly chitinized and the lateral parts, weakly chitinized. 

 The postscutellufu also may be distinguished as a narrow, 

 weakly-chitinized, curving bar, running laterad on each side 

 just in front of the caudal apex of the scutellum. The 

 prcBscutum is represented merely by a thin, transversal strip 

 of membrane. 



Ventral aspect. — As with the prothorax the ventral 

 aspect of this segment is composed of the sternum and the 

 pleural sclerites. 



Mesosternuni. — The mesosternuin is plainly set off by 

 sutures. Its caudal margin has a broad, median tongue, 



