Casey — A Revision of the American Paederini. 71 



Eyes normally developed; neck never less and frequently more than half as 

 wide as the head; prosternum short and broad before the coxae; labrum 

 short, reclilinearly truncate at apex, with a rounded median sinus, the 

 lobes broad and feebly oblique at their apical margin; antennae varia- 

 ble, stout to rather slender; head broadly arcuato -truncate at base. . 9 



9 — Body parallel, more or less stout, the gular sutures nearly straight, 



feebly converging from apex to base, near which they are most approx- 

 imate, sometimes widely separated and parallel; head well developed 

 but never wider than the elytra; prothorax oblong, with the anterior 

 angles more or less distinct; elytra generally shorter in the male than 

 in the female; body large to moderate in size, the sculpture rather 

 coarse and sparse, except that of the abdomen which is minutely 



punctate. Cosmopolitan Lathrobinm 



Body slender and fusiform, moderate in size, sculptured nearly as in 

 Lathrobium; gular sutures parallel, arcuate, generally widely separated 

 and most approximate at or slightly before the middle of the post- oral 

 surface ; head small ; prothorax oblong, with the apical angles moder- 

 ately distinct; elytra larger than in Lathrobium. America.. Litolathra 



10 —Gular sutures rather widely separated, parallel and straight to the base. 



Body slender, normally convex, the head well developed but not as wide 

 as the elytra, broadly arcuato -truncate at base, with broadly rounded 

 angles, the neck a little less than half as wide, the eyes rather small but 

 unusually convex and prominent; labrum obliquely bilobed, the lobes 

 rather narrowly rounded at tip ; maxillary palpi rather short but nearly 

 as in Lathrobium, the third joint obconic; antennae moderately thin, the 

 joints elongate, subcylindric, rather rapidly narrowed at base ; proster- 

 num rather long in front of the coxae; prothorax oblong -elongate, with 

 the angles distinct, the elytra oblong, parallel, with prominent basal 

 angles and feebly subserial punctures, longer and wider than the pro- 

 thorax; abdomen parallel, the sides straight, the sculpture very fine and 

 dense; legs short, moderately stout; body small in size. Europe. 



*Tlirobalium 



Gular sutures parallel and arcuate, rather widely separated, most approxi- 

 mate at or near the middle of the post-oral surface; labrum broadly, 

 obliquely bilobed, the apex broadly and subangularly emarginate 

 throughout the width 11 



Gular sutures very widely separated, mo-tt approximate anteriorly, thence 

 gradually diverging to the base where they are most remote; labrum 

 narrowly, deeply and angularly cleft in the middle, the lobes each sub- 

 quadrate in form with its apex obliquely truncate 12 



11 — Body parallel, moderately slender and decidedly depressed, small in 



size, the head subquadrate, rectiliuearly truncate at base throughout 

 the width, the angles right and not evidently rounded; eyes moderately 

 developed, slightly prominent; maxillary palpi short, the third joint 

 inflated toward tip; antennae rather long, moderately stout, the joints 

 obconic; neck wide, three-flfths as wide as the head; prosternum short 

 before the coxae; prothorax short and broad, with the apical angles 

 well defined, the polished median line being defined by series of punc- 

 tures; elytra oblong, longer and wider than the prothorax, with well- 



