18 
NORTH AMERICAN THROSCIDAE 
The shorter measurement applies to an exceptionally small 
male. This species appears to be the most common one from 
the Mississippi Valley to the Atlantic. The name was given by 
Say to “our insect” without any adequate description, he appar- 
ently having known but one species. In his Monograph, Bon- 
vouloir described and figured the male under this name, but in 
a supplementary publication he described the female received 
from Dr. Schaum as a type of Say’s species, and substituted the 
name alienus for the previously described male, which he says is 
very near but is really distinct. 
The simple antennal club, little different in the sexes, the long 
prosternal striae and almost entire margin, and the form nar- 
rowed behind must be relied upon for the separation of this 
species. 
New Hampshire, Vermont, Massachusetts, New York, Penn- 
sylvania, New Jersey, District of Columbia, Virginia, Michigan, 
Wisconsin, Minnesota, Illinois, Ohio, North Carolina, Georgia, 
Florida and Arkansas. One specimen labeled “Or.” I think is 
open to doubt. 
[A. rugosiceps Schaeffer probably comes in here. See remarks 
following table of species. H. C. F.] 
9. Aulonothroscus detritus new species 
Very small, pale reddish brown, shining, shghtly narrowed behind, clothed 
with fine and coarse hair. Head convex, finely punctate; eyes small, entire 
and widely distant, orbits very finely impressed, intra-antennal ridges feeble. 
Thorax not very convex, feebly bi-impressed at base, nearly one-half wider 
than long, in front as wide as long, sides broadly arcuate, margin fine, scarcely 
more than one-half, obtusely carinate at hind angles, disk very finely, sparsely 
punctured, the punctures larger toward the sides and very much larger toward 
the hind angles; base at middle feebly lobed, broadly sinuate each side, hind 
angles prolonged. Scutellum as usual small, truncate in front, arcuate each 
side, as broad as long. Elytra not much more than twice as long as wide, feebly, 
obliquely impressed behind the humeri, sides broadly arcuate and slightly 
narrowed behind, rather obtuse at tip; striae extremely fine, with distant, 
minute punctures becoming more evident at tip; intervals with very fine, 
sparse, mostly uniseriate punctures. Prosternum narrow, striae parallel, 
abbreviated by about one-fourth, a few minute punctures anteriorly, punctures 
coarser on flanks of prothorax and sides of metasternum, a short transverse 
row on first ventral at sides; middle of metasternum minutely, sparsely punc- 
tate, a little more coarsely in front. Abdomen finely, sparsely, variolate 
punctate, a little more coarsely on last ventral. Length 1 .8 mm. 
The hind angles of the prothorax are not at all dilated and I 
think the one specimen is probably a female. The antennal 
