Casey — A Revision of the American Paederini. 97 
punctures fine and sparse; abdomen nearly as wide as the elytra. Male 
with the secondary sexual characters as in confusa, except that the 
apex of the sixth ventral is much more broadly and feebly rounded, 
with the triangular notch smaller, being about a third as wide as the 
apex and but little wider than deep. Length 5.6 mm.; width 0.9 mm. 
New York (near the city) and District of Columbia..... suspecta 0. sp. 
The three distinct groups of species in the above table are 
represented by concolor, cruralis and confusa, the first two, 
composed of larger species, having the elytra large, the last, 
with the elytra small, being composed of a considerable num- 
ber of much smaller species. The fact stated of certain 
species of Lathrobium, that the female is smaller and more 
slender than the male, is still more obvious in this genus, Deiig 
strikingly apparent in cruralis and confusa. 
Lathrobiopsis n. gen. 
We begin in this genus a series of groups, well distin- 
guished from those which precede by the longer basal joint 
of the hind tarsi, this being as long as the second in the 
present genus and both slightly elongate. In addition to 
this, the first joint is similar to the second beneath and not 
swollen into a flattened sole. Lathrobiopsis differs very 
greatly from Lathrobioma, which has more the facies of 
Lathrobium, in its depressed form and small prothorax, with 
the median smooth line partially delimited by impressed series 
of punctures, large flattened elytra, with regular series of 
punctures and in other characters as shown in the table; our 
single representative at present is the following : — 
Body slender, distinctly depressed, dark testaceous, the head dusky, the 
abdomen piceous-black; legs pale flavo-testaceous, the antennae dusky 
rufous; head quadrate, the sides long, parallel and nearly straight, the 
basal angles very distinctly right and but very slightly rounded; punc- 
tures rather coarse, deep, moderately sparse, a small vertexal space 
impunctate; antennae stout, longer than the head and prothorax, the 
medial joints one-half longer than wide, inflated and rounded at the 
sides and pedunculate at base; prothorax very slightly narrower 
than the head, not longer than wide, the sides evidently converging 
from apex to base and nearly straight, the apical angles distinct and 
not rounded, the punctures not quite as coarse as those of the head, 
confused and moderately sparse except along the broad impunctate 
