220 «5E0. H. HORN, M. I>. 



thoi-ax not wider than the head, longer than wide, slightly narrowed posterior)}' ; 

 sides distinctly sinuate, median smooth space rather narrow, punctures at the sides 

 coarse and not closely placed ; elytra a little wider than the thorax but not longer, 

 as wide conjointly' as long; surface densely punctured but slightly shining, sparsely 

 pubescent; abdomen very densely and finely punctulate and sub-opaque, sparsely 

 pubescent; beneath densely punctulate, a little more shining than above. Lengtli 

 14— .Ifiinch; 3.5 — 4 mm. 



Sexual characters as in ci'iifrrjsreiis. 



This species resembles the preceding, but has the head and thorax 

 more coarsely and less densely punctured. The elytra are also less 

 opaque, and are not longer than the thorax as in tuniiis. 



(Occurs in iNIichigan and the New England States. 



.4. f rsitcrciiliis n. sp. — Slender, elongate, parallel, rather depressed, piceous, 

 sub-opaque; elytni brownish; antennae pale brown, shorter than the head and 

 thorax, joints 8-10 as wide as long; head quadrangular, coarsely but sparsely 

 punctate, a median smooth space; beneath punctate and alutaceous; thorax not 

 wider than the head, oblong oval, longer than wide, very little narrower behind ; 

 sides scarcely sinuate; surface coarsely but not closely punctate, a moderately 

 broad median smooth space; elytra a little wider and very distinctly longer than 

 the thorax, longer than wide conjointly, parallel, sub-depressed, moderately densely 

 punctured, sub-opaque, finely pubescent; abdomen finely, moderately densely 

 punctate, sub-opaque, finely pubescent ; beneath more coarsely and less densely 

 punctured ; legs piceo-testaceous, or testaceous. Length .14 inch ; 3.5 mm. 



Male. Anterior tarsi moderately dilated ; last ventral segment with oval emar. 

 gination. 



Female. — Anterior tarsi slightly dilated ; last ventral entire. 



Occurs in northern Illinois and Michigan. 



This and the two preceding species form a small group, very natu- 

 rally related and not easy to separate. 



A. nanus is rather larger, and has more tVie form of ci'uej-ascens, the 

 thorax broader in comparison with its length, and more decidedly oval, 

 the sides more arcuate. The elytra are obviously longer than the thorax.. 



A. inntilis is slender, but more convex than the next species. The 

 thorax is a little longer than wide, and very plainly narrower behind. 

 The elytra are not longer than the thorax, and are nearly as wide as long. 



A. fratercuhis is more slender and depressed. The thorax very dis- 

 tinctly longer than wide, in fact oblong oval, and scarcely visibly nar- 

 rower behind. The elytra are relatively longer than in the preceding 

 species, longer than the thorax, and nearly a third longer than wide con- 

 jointly. 



A. senilis n. sp. — Slender, piceous, nearly black ; antennae shorter than the 

 head and thorax, piceous, joints 4-10 as wide as long, the outer ones a little wider : 

 head quadrangular, moderately densely and rather coarsely punctured, a small 

 smooth space on the vertex; beneath sjiarsely coarsely punctured; thorax not 



