10 
GEO. H. HORN, M. D. 
Punctuation of under side coarser, its double character very evident. 
Of this scarificatus and limhatus Mann, are feeble varieties, and pi- 
cescens Lee. a synonym. Alaska, Oregon, Hudson’s Bay, Dacota, 
Idaho, Utah, Montana, Colorado, New Mexico, Lake Superior, 
Canada, Labrador, New Hampshire. 
On comparing these forms with abbreviatiis and impressicollis, it 
will be observed that the vestiture is finer and sparser, the scutellum 
nearly glabrous. The thorax is always more sparsely and finely 
punctured. The form is also less convex and more elongate. 
Candeze states (Mon. iii, p. 68) that riparius Fab. occurs in the 
polar regions of our continent. I have not seen any specimens that 
I am willing to refer to that species, although some of the forms of 
iuciduhis have the dorsal striie so feebly punctured that they might 
l)e considered smooth. The study of the material before me leads 
to the thought that all the species from the Arctic regions of both 
continents need a renewed study with a larger number of specimens 
than seems to have been used. 
Group SQUALIDUS. 
Prosternal sutures straight and parallel, or very slightly conver- 
gent posteriorly. Maxillary palpi not prominent, the terminal joint 
triangular. Legs slender and moderately long, the tibiae not spinu- 
lose, the terminal spurs small and inconspicuous. Form oblong, 
much depressed ; surface opaque, densely punctured, sparsely pubes- 
cent. Body distinctly winged. 
This group is represented in our fauna by three species, and a 
fourth (depres-nis) from Siberia should probably be referred here. 
The flattened form and opaque surface are repeated in the driaialus 
series, but these have the strongly arcuate prosternal sutures. 
The three species are as follows ; 
Antennfe and legs always pale; under side of body finely pubescent with longer 
scale-like hairs sparsely scattered sqiialitlus. 
Antennae and legs piceous, sometimes the tibije are pale; vestiture of under side 
uniform. 
Surface very opaque liiiiebris. 
Surface slightly aeneous plaiiatus. 
C’. squalidus Lee. — Oblong, piceous black, opaque, sparsely clothed with 
very short brownish pubescence, with silken yellow sparsely intermixed : head 
coarsely, not closely punctate : antennse not reaching the hind angles of the 
thorax, feebly serrate, joints all longer than wide, the eleventh but little longer 
than the tenth ; thorax longer than wide, distinctly narrowed in front, sides 
regularly arcuate, sinuate in front of the hind angles, these slightly divergent, 
