Casey — A Revision of the American Paederini. 235 
margin; hind tarsi rather elongate but distinctly shorter than the 
tibiae, the basal joint much elongated but shorter than the remain- 
der; head more or less broadly arcuato-truncate at base; sculpture 
only moderately coarse, the head and pronotum strongly punctato- 
reticulate, the elytra and abdomen asperately punctate; body more 
or less slender. Europe, Asia and North America...........-Sunius 
Labrum advanced and prominent toward the middle, the teeth moderate in 
size, broadly triangular, each with a longer and very slender seta project- 
ing from its apex, the teeth separated by a moderate emargination, the 
transverse bottom of which bears two very minute approximate den- 
ticles, each of which has a long slender tactile seta projecting from its 
apex; just without each of the principal teeth there is a small, angulate 
emargination of the edge; prosternum long, nearly flat, not transversely 
tumid but with a very small cariniform elevation paralleling and close 
to the apical margin, the median line from this carina to the coxae 
strongly carinate; posterior tarsi short, very much shorter than the 
tibiae, the basal joint much elongated and as long as the entire remain- 
der; anterior tarsi of the male thicker though scarcely dilated, the sub- 
apical joints somewhat obliquely united, — suggesting Pinophilus; 
head prolonged and strongly rounded at base; sculpture of the head 
and pronotum consisting of Jarge reticulations of somewhat feeble lines, 
of the elytra of distinct, rather coarse and sparse impressed punctures, 
the abdomen obsoletely and very finely, sparsely punctulate. Central 
BIIOTICR Fido ion ci en ken ew steers uvesiceicnticeicitdcnscves* DipOlonetes 
The diagnosis of Nazeris Fauv., has been taken from a 
female of pallidipes Reit., and that of Dibelonetes Sahl., from 
the male of a form which appears to constitute a variety of 
the Central American fragilis Shp., from San Marcos, 
Nicaragua. 
I greatly regret not being able to study the genus Céeno- 
mastax Kr., in order to determine its relationships, but this 
remark also applies to several other described genera. 
Sunius Erichs. 
Numerous species of this genus, frequently closely allied 
among themselves, occur throughout the continent and are 
everywhere plentiful in individuals. They have in common 
avery monotonous uniformity of habitus which, in connec- 
tion with their small size, has caused them to be greatly neg- 
lected by systematists. The ornamental coloration of many 
forms is highly inconstant, especially so in the Texan incon- 
stans, and, in americanus and some others, the abdomen, 
