COEEOPTERA. 167 



Delaware, 1. 



Although somewhat resembling arculus Er., this species may be 

 distinguished by the structure of the antennae and tarsi, as well as 

 by the punctuation and general structure of the interocular surface. 



13. A. flavicorilis (Er.). — Form rather slender, very feebly depressed. 

 Pubescence rather sparse, moderate in length, cinereous, fine, more recum- 

 bent, and dense on the abdomen. Head large, robust, scarcely twice as wide 

 as long; interocular surface very feebly depressed, three-fourths wider than 

 the eye, rather finely, uniformly, very closely, and deeply punctate ; punc- 

 tures not coalescent, round; surface most deeply impressed near the eyes, 

 gradually rising to the middle, which is broadly and rather feebly convex ; 

 ocular lines meeting at three or four lengths in advance, very feebly conver- 

 gent, nearly straight ; antennae long, very slender, flavo-testaceoiis through- 

 out, club moderate ; third joint much more than one-half longer than the 

 fourth, eighth much elongated, all translucent ; maxillary palpi very long 

 and slender, piceo-testaceous throughout. Prothorax arcuately, evenly, and 

 rather rapidly increasing in width to a point distinctly in advance of the 

 middle, where it is nearly one-eighth narrower than long and about three- 

 fourths as wide as the head; sides thence rather strongly convergent poste- 

 riorly and nearly straight ; anterior and posterior margins nearly equal in 

 length, very feebly and equally arcuate ; surface nearly evenly convex, 

 nearly evenly, closely, finely, and deeply punctate, nearly impunctate in 

 the middle. Elytra at base slightly narrower than the head ; sides very 

 feebly divergent posteriorly, distinctly longer than the width at base, feebly 

 areiiate, more strongly so posteriorly ; together broadly, roundly, and some- 

 what strongly emarginate behind ; suture nearly one-fourth longer than the 

 pronotum ; surface very feebly impressed on the suture toward the base; 

 punctures round, rather small, deeply impressed, nearly evenly distributed, 

 often distant by more than twice their widths ; interspaces nearly flat, 

 polished, finely reticulated. First four abdominal segments equal in width, 

 distinctly narrower than the contiguous elytra, cylindrical, constricted at the 

 base ; surface finely, closely, and evenly punctulate, much more finely so 

 toward the apex ; border obsolete except on the first segment ; transverse 

 carinae not cusped ; the second segment is perhaps very slightly narrower 

 than the fourth. Legs very robust, pale piceo-testaceous, tips of the poste- 

 rior femora darker, tips of the tarsal joints slightly darker ; first joint of the 

 posterior tarsi as long as the next two together ; fourth joints very strongly 

 bilobed, lobes robust ; coxae piceous-black. 



Male. — Posterior edges of the second, third, and fourth ventral segments 

 very feebly emarginate in the middle fifth, emarginations extremely feeble, 

 rounded, and increasing in strength posteriorly, being nearly straight on the 

 second, and very distinctly curvate on the fourth ; fifth segment entire ; sixth 

 deeply sinuate at apex, sinus narrower and more acutely rounded than the 

 apices, slightly deeper than wide ; seventh very broadly, roundly, and some- 

 what strongly emarginate at tip. 



