314 COLEOPTERA OP NORTH AMERICA. 



more extended observation, the group as here defined contains 

 all those genera in our fauna in which the eyes are finely granu- 

 lated, deeply emarginate, with the upper lobe wide; the scutellum 

 acute, but not very large, though sometimes elongate; and the 

 prothorax not distinctly lobed, but only feebly bisinuate or trun- 

 cate at base. The antennas are more slender than in Trachyderes, 

 and the poriferous system is much less distinct, or even obsolete, 

 though in Stenaspis it is still quite obvious, and the joints are 

 carinate and bisulcate. In Batyle the last joint of the palpi 

 (which is subcylindrical, and truncate) is very feebly impressed. 



The antennal tubercles are either much elevated, leaving a 

 concavity between them, or scarcely elevated, in which case the 

 vertex is nearly flat ; the front in the former is very large, square, 

 and perpendicular, and the gense are long; in the latter the tuber- 

 cles are less elevated, the front is moderate, declivous, and the 

 gente usually short. 



They may be thus tabulated : 



A. Front large, square, perpendicular, abruptly separated from the ante- 



ocular spaces ; ' 

 Prothorax bituberculate at the sides, body glabrous ; 



Mesosternum protuberant. STEKASPIS. 



Prothorax armed with a lateral spine ; mesosternum not protuberant ; 



Body pubescent. TRAGIDION. 



Body glabrous. PURPCTRICENUS. 



Prothorax rounded, convex. AETHECERUS. 



B. Front moderate, short, declivous, not abruptly defined each side ; 



Two ivory vittse on each elytron ; 



Mesosternum declivous ; (prothorax margined at apex). 



MANNOPHORUS. 



One ivory vitta on each elytron ; 

 Mesosternum protuberant ; (prothorax not margined at apex). 



ENTOMOSTERNA. 



Elytra without ivory vittse ; mesosternum declivous ; 

 Body pubescent, prothorax not margined at apex. AMANNUS. 

 Body pilose, prothorax margined at apex. BATTLE. 



Of the three species of Tragidion, two have the elytra sulcate, 

 while T. armatum has them even : there is also a difference in 

 the hind tarsi, which are comparatively wider in T. annulatum. 

 Variations in the proportions of the joints of the hind tarsi are 

 not unusual in Cerambyoidae, as, for instance, in Criocephalus. 

 This fact has induced me to refer Spheenothecus cyanicollis to 



