NORTH AMERICAN COLEOPTERA. 
333 
Male — Front greenish, snbopaque, very indistinctly punctate, 
sparsely pubescent. Prosternuin closely punctate, sparsely hairy. 
Metasternuin slightly jiubescent in front. Abdomen slightly flat- 
tened at middle of first two segments, rather roughly sculptured, 
not hairy. 
Feiaale . — Front brassy, more shining, feebly punctate, not ])ubes- 
cent. Prosternum rather sparsely punctate, not hairy. Abdomen 
convex at middle, sparsely punctate. 
No variations have been observed. While resembling very closely 
imbelHs, it will be at once known by the feeble sculpture of the head 
in both sexes, the median depression of the thorax and the sexual 
characters. 
Hub — Western Nevada (Morrison). 
.4. piisilliis Say. — Form of aclimiuutive rujicollis ; head and thorax usually 
seueous or cupreous, elytra purple-hlack (but variable), moderately shining. Au- 
teunse reaching the middle of the thorax, piceous, serrate from the fifth joint, 
serrate joints wider than long; head convex, a feeble median impression from 
the occiput to the base of the clypeus, surface moderately closely coarsely punc- 
tate. Thorax wider than long, slightly narrowed at base, sides arcuate in front, 
slightly sinuate near the hind angles, which are rectangular and distinctly cari- 
nate. margin nearly straight, deflexed in front, disc convex, a broad transverse 
depression in front of base, so that, when viewed laterally, the median line of 
the thorax is more convex in the anterior half, lateral oblique depression mod- 
erately deep, surface moderately coarsely transversely strigose, with coarse punc- 
tures in the grooves; scutellum carinate or not; elytra sinuate at the sides, 
distinctly dilated behind the middle, apices rounded, serrulate ; disc flattened, 
usually a vague costa on each side, a feeble concavity each side of the suture, 
basal depressions feeble, surface with imbricate sculpture, not rough nor close; 
body beneath piceou.s, shining, faintly bronzed; prosternal lobe truncate and 
broadly emargiuate, the intercoxal process acutely oval at tip, propleurse punc- 
tate and strigose; metasternum at sides strigose and subreticulate. Abdomen 
sparsely finely punctate, a little more coarsely at the side of the first segment; 
pygidium sparsely punctate, not carinate ; claws broadly toothed. Length .12 — 
.16 inch. ; 3 4 mm. 
Male . — Front flatter and more opaque; flrst ventral slightly flat- 
tened at middle and rugose. 
F emale . — Front more shining and rather more convex ; first ventral 
convex and not roughened. 
Variations . — The general aspect of this species is that of a diminu- 
tive rujicollis with the thorax less conspicuously cupreous. The tho- 
rax is often brassy with purplish spaces at the sides. Sometimes the 
elytra are seneous. These last forms resemble jjutillus, but these 
have no carina in the hind angles of the thorax, and the disc has a 
distinct median impression. 
