Casey — A Revision of the American Paederini. 211 



Scopaeoma n. gen. 



In a certain sense this genus and the two following form a 

 group differing greatly from the broad-necked genera in some 

 peculiarities of sculpture. In Oi-us and related genera, the 

 punctures of the pronotum are very much larger as well as 

 sparser than those of the head, while in Scopaeoma, Scopae- 

 opsis and Scopaeodera, the thoracic punctures are, when pres- 

 ent at all, equal to or smaller and sparser than those of the 

 head; but in the first alone are they distinctly visible. In the 

 second all the punctures become so minute as to be nearly in- 

 visible and entirely filled by the bases of the fine hairs consti- 

 tuting the pubescence, while in the last the punctuation be- 

 comes wholly lost and the surface glabrous. The present 

 genus approaches Scopaeus more closely than the other two 

 in the nearly parallel and less convex form of the body and in 

 the much shorter and somewhat thicker tarsi, with a form of 

 the prothorax nearly similar to that of Pycnorus. The species 

 are moderately numerous and extend over the entire northern 

 part of the continent from the Atlantic to the Pacific, those 

 known to me being distinguished as follows : — 



Head almost semicircularly rounded at base, smaller in size and relatively 



more elongate 2 



Head large, broadly truncate at base, scarcely at all longer than wide... 5 



2 — Head distinctly wider than the prothorax 3 



Head subequal in width to the prothorax, never more than very slightly 



wider 4 



3 — Body slender, black, the legs pale brown throughout, the punctures fine 



and dense, less dense on the pronotum than on the elytra: head elon- 

 gate, broadly concave between the antennal prominences. Male with a 

 large oval concavity at the apex of the fifth ventral and a subquadrate 

 emargination formed in part by short prolongations of the sides of the 

 concavity, the floor of the concavity smooth, with a narrow, slender, 

 posteriorly inclined, acutely attenuate spine, bearing at each side near 

 its apex a short seta projecting laterally; sixth segment with a simple 

 subparabolic sinus wider than deep and about a third as wide as the 

 segment; middle tibiae somewhat abruptly thickened from behind the 

 middle to the apex. Length 2.9 mm. ; width 0.5;mm. Vancouver Island. 



brnuuipes Lee. 



Body parallel, rather convex, shining, black or slightly piceous in color, the 



legs piceous-black with the tarsi pale brown, the antennae dark brown* 



