NORTH AMERICAN COLEOPTERA. 
1 
lo 
angles, which are stout, slightly everted, and with a short carina ; disc feebly 
convex, densely finely punctate, the median line usnally smooth, but not always ; 
elytra as wide as the thorax, humeri obtuse, sides nearly parallel for two-thirds 
then arcuate to apex ; disc rather fiat, striate, equally from middle to sides, strife 
punctate, intervals feebly convex, densely and finely punctulate, the surface 
opaque; prosternum moderately closely punctate, more densely and finely at the 
sides, the lobe short and subtruncate, the transverse impression distinct ; pro- 
pleni’se closely finely punctate, not opaque ; metasternum and abdomen densely 
punctate, a little more closely than the propleurse. Length 3 — 4 mm. ; .12 — .16 inch. 
An easily known species by the group characters alone. In some 
specimens the basal joints of the antenne are somewhat paler, but 
these specimens have the under side somewhat paler also, and are 
probably less mature. 
The distribution of this species is rather remarkable. Originally 
described from the Lake Superior region, it extends westward to 
Oregon (Wickham) and northern California, eastward to Ohio 
(Dury) and Allegheny, Pa (Hamilton). 
Group CHORIS. 
Prosternal sutures arcuate and convergent posteriorly. Maxillary 
palpi moderately prominent, the last joint elongate triangular. Form 
convex. Elytra deeply striate, more or less ornate. Thorax roughly 
granulate, the median line usually finely elevated and smooth ; sur- 
face more shining. 
The species of this group seem naturally to fall together by the 
very rough sculpture of the entire surface of the thorax. In the 
dermestoides group the thorax is somewhat granulate in front, but 
comparatively smooth posteriorly. To this group belong pxdchelhis 
and sahxdieola, probably also curtus and alysidotus of the European 
fauna. 
The species known to occur in our fauna may be separated in the 
following manner : 
Apical margin of thorax truncate at middle. 
Form gibbous, strongly arched when viewed laterally; carinse of hind angles 
short ; entirely pale above cleliinibis. 
Form normal, not very convex; cariufe of hind angles long; color black, or- 
nate with yellow. 
Antennae with three basal joints pale yellowish testaceous; legs always 
entirely pale clioris. 
Antennse piceous, very little, if at all, paler at base; legs with the femora 
at least fuscous or piceous. 
Elytra gradually attenuate in their posterior third.. exiguus. 
Elytra not attenuate, ape.x obtuse oriiatiis. 
Apical margin of thorax arcuate at middle, slightly prolonged over the head and 
somewhat elevated Cliciillatus. 
