Casey — A Revision of the American Paederini. 23 
to the base, the basal part of the intermediate surface elevated above 
the general level; basal joint of the antennae shorter than usual, being 
scarcely one-half as long as the width of the head; prothorax slightly 
broader near the base than at apex; elytra longer and wider than the 
prothorax, parallel; abdomen as wide as the elytra, conically tapering 
from the apex of the fourth segment; legs moderate, the tibiae strongly 
spinulose, the hind tarsi long and slender with the basal joint almost 
as long as the next two combined and much longer than the fifth; in- 
teguments smooth, polished and sculptureless above, except the basal 
parts of the head and the abdomen, which are feebly micro-reticulate, 
the head and pronotum rather finely, very sparsely punctate, the elytra 
with widely separated even unimpressed series of extremely fine feeble 
setigerous punctures. BraZil.....esssccescccesscccceseee *Aderovium 
Neck distinctly and abruptly constricted across the dorsal surface; sculp- 
ture strong and distinct, the punctures simple......-sesseseereereee 5 
- §— Antennal joints not constricted at base, obconical, shorter and broader 
toward tip; elytral suture strongly beaded. Body parallel, moder- 
ately convex, moderate to large in size; head oblong, parallel, inflated . 
or narrowed behind the eyes which are well developed, finely faceted, 
more or less prominent and anterior, the post-ocular foveolae well de- 
veloped; neck broad, three-fifths to three-fourths as wide as the head, 
the basal angles of the latter only very rarely obliterated; mandibles 
tridentate within, the two lower teeth on a broad common base and 
equal in size, more developed on the left mandible; labrum edentate, 
short, biobliquely truncate with a shallow rounded median sinus; basal 
joint of the antennae relatively very moderate in length, not as long as 
the next three combined; gular sutures fine, becoming very approxi- 
mate behind the middle; lobes of the ligula rounded, coriaceous or 
membranous, separate; mentum trapezoidal, large, feebly convex, coria- 
ceous in apical half; prothorax rather small, ob’ong, always nar- 
rower than the head; elytra greatly developed, always longer and wider 
than the prothorax, usually elongate; abdomen seldom quite as wide as 
> the elytra, the sides parallel, the segments feebly impressed at base; 
legs moderately long, slender, the hind tarsi elongate with the basal 
joint usually distinctly shorter than the next two combined but about as 
long as the fifth. Male with the subbasal ventral segments modified by 
discal foveae or short transverse setose furrows, the third segment 
lobed in the middle at apex, the lobe very variable. North and South 
AMCTICAs oscccciecce cccdcdvccecs vances cccces secs eccecns QEARtFOIODIUM 
Antennal joints not constricted or compressed at base, the elytral suture 
strongly beaded. Body parallel or anteriorly attenuate, moderately 
convex; head oblong, parallel, inflated or gradually narrowed behind 
the eyes, sometimes notably small, the neck broad, three-fifths to three- 
fourths as wide as the head, the basal angles rounded to the neck or 
obliterated; mandibles bidentate within; eyes moderately large, an- 
terior, more or less prominent, the facets fine and feebly convex; 
labrum short, biobliquely truncate, edentate, with a small shallow 
rounded median sinus; basal joint of the antennae elongate, as long as 
the next three or four combined; post-ocular setigerous punctures well 
developed; gular sutures fine and feeble, narrowly separated, most ap- 
