Casey — A Revision of the American Paederini. 225 



width to the latter; legs rather long and slender. Male with the fifth 

 segment rectilinearly truncate at tip, with a gradually formed short 

 and acute median lobe in the form of a cusp, occupying about median 

 eighth or ninth of the width, the sixth segment with a simple rounded 

 sinus occupying about half the apes and fully four times as wide as 

 deep. Length 3.8 mm.; width 0.82 mm. New York, Virginia, Iowa, 



Missouri and Texas (Austin) dentatus Say 



Median smooth line broader and more conspicuous; abdomen very sparsely 

 punctulate and polished; elytra finely and sparsely punctate and strongly 

 shining but never metallic in lustre ; punctures of the head and pronotum 

 rather coarse and strongly, longitudinally confluent 11 



11 — Elytra large, slightly wider than the head 12 



Elytra small, evidently narrower than the head. 13 



12 — Form moderately stout, blackish-piceous in color, the elytral apex 



and legs throughout pale luteo-flavate, the antennae pale rufous; 

 head somewhat longer than wide, rather broadly ogival behind the 

 eyes, the latter convex and prominent, at their own length from the 

 base measured longitudinally; antennae rather thick, distinctly 

 incrassate distally; prothorax nearly as in deritatus, two-thirds as wide 

 as the head; elytra scarcely as long as wide, slightly wider than the 

 head, parallel, two-thirds wider than the prothorax and a third longer; 

 abdomen at base obviously narrower than the elytra, the third and 

 fourth segments as wide as the head; legs only moderately long and 

 slender. Male with the apex of the fifth ventral broadly, feebly sinuate 

 in median third, with a broad and obtusely angulate tooth gradually 

 formed at the bottom of the sinus, the surface of the process slightly 

 tumid and polished; sixth segment broadly, cylindrically impressed 

 along the middle, with an apical sinus nearly a third as wide as the seg- 

 ment and about twice as wide as deep, subtriangular in form but with 

 the angle distinctly rounded. Length 3.75 mm. ; width 0.78 mm. Rhode 



Island (Boston Neck) luculentus n. sp. 



Form and size nearly similar to luculentus but deep black throughout, the 

 elytra and abdomen highly polished, very finely, sparsely punctured, the 

 former without paler apex except very faintly toward the external angles, 

 the femora and tarsi pale honey- yellow, the former toward tip and the 

 entire tibiae picescent, the antennae dusky ; head nearly similar but more 

 broadly and obtusely ogival at base, the eyes larger and at less than 

 their own length from the base; autennae more slender and less in- 

 crassate; prothorax nearly similar; elytra quadrate, parallel, fully 

 as long as wide, only just visibly wider than the head, three-fourths 

 wider and two-fifths longer than the prothorax; abdomen nearly as in 

 the preceding, the legs rather longer and more slender. Male unknown. 

 Length 3.6 mm.; width 0.75 mm. Mississippi (Vicksburg). 



nigrolnceus n. sp. 



13 — Form somewhat similar to the two preceding, smaller in size, black in 



color throughout, the elytra and abdomen highly polished and sparsely 

 punctulate, the former pale only at the external apical angles, the legs as 

 in nigrolucens, the antennae moderately slender, distinctly incrassate and 

 somewhat paler rufous; head rather acutely ogival behind the eyes, 

 which are very large, convex and prominent and at scarcely their own 



