134 Journal New York Entomological Society. [Voi. vii. 



3 — Clypeus extremely short before the rather large and well-developed eyes, truncate 

 with rounded angles, the antenna; inserted under its sides adjoining the eyes, 

 straight, the club small, with the three joints equal in length ; prosternuni trans- 

 versely convex, not carinate, broadly and gradually deflexed, forming a protection 

 to the mouth in repose ; metacoxal arcs complete, the first suture nearly obliterated 

 at the middle ; tarsal claws cleft at the middle Stethorus 



Clypeus prolonged for a considerable distance before the eyes, the sides converging, 

 the antenna; inserted in very small shallow emarginations just befoi'e the eyes. .4 



4- Last joint of the maxillary palpi narrow, obliquely pointed at lip ; antenna; bent, 

 with the club well developed, the head very small, with well -developed eyes ; 

 prothorax much narrower than the elytra ; prosternum rather narrowly separating 

 the coxae, with two short feeble carina;, gradually and feebly deflexed toward 

 apex but not affording protection to the mouth ; metacoxal plates entire . . Didion 



Last joint of the palpi large and normally securiform ; antennae with the club moderate ; 

 prosternum flat, not at all deflexed toward tip, generally bicarinate 5 



5 — Head exserted and moderately deflexed, the eyes small and not attaining the an- 

 terior margin of the prothorax, which is parallel at the sides ; antenna; well- 

 developed and straight ; prosternum flat, with two distant parallel and entire 

 carina; ; metacoxal arcs short, widely incomplete, not extending to the first 

 suture ; body parallel and straight at the sides Selvadius 



Head inserted within the prothorax, the eyes well developed and partially covered ; 

 antennce shorter and bent ; body more or less oval, the prothorax narrowed in 

 front, the prosternum and metacoxal arcs varying subgenerically Scy mnus 



6 — Metasternum with a large circular and densely pubescent pit near each lateral mar- 

 gin ; body oblong-oval, rather depressed, pubescent ; metacoxal plates entire ; 

 eyes oval, entire or virtually so, somewhat prominent and barely attaining the 

 prothorax ; maxillary palpi very long ; first two tarsal joints short, the last long, 

 the claws well developed and simple CephaloscyiTinus 



These genera are all very widely distributed, except Didion and 

 Selvadius, which are founded upon local types. Cephaloscxmnus is a 

 remarkably aberrant and specialized form, but its general affinity with 

 Scy mnus is sufficiently evident. 



Smilia Weise. 

 These are small, apparently glabrous species, formally assigned 

 to Pentilia ; they inhabit the entire territory of the United States. 

 Those thus far discovered may be identified as follows : — 



Elytra uniform in coloration throughout, the suture finely and distinctly margined. . .2 



Elytra bicolored, each having a large oval red spot ; sutural margin " not dis- 

 tinct " 6 



2 — Head transverse, the clypeus broader and shorter, rapidly expanding before the 

 antennal sinus 3 



Head but little wider than long and perfectly flat throughout, the clypeus narrower 

 and more prolonged ^ only very feebly expanding before the antennoe ; species 

 very minute, black, the pronotum minutely reticulate and alutaceous but not dis- 

 tinctly punctured 5 



