198 
IOWA ACADEMY OP SCIENCES. 
species of the second group have longer pronotum, longer, nar- 
rower elytra, with an appendix, never possessing reflsxed veins. 
Here is placed debilis^ which is closely related to the European 
a'^dominalis and melscheimeri, which is intermediate between the 
European notatus and striatus. The group is nearly unicolor- 
ous, without distinct markings; the larvae are uaicolorous, usu- 
ally yellowish in color. The third group, of which inimicus is 
the best known, have shorter, rounding, more centrally pro- 
duced heads, with a row of points on the anterior margin of the 
vertex, extending down to the antennae on either side. The cen- 
tral ante apical cell is constricted in the middle and divided by 
a short nervure. They are closely related to the European 
pulicarius, and, like that species, not typical Deltocephalids. 
They are of a general dark color, more or less maculate. The 
known larvae are dark margined or banded. 
It has been thought best to place this group here for the 
present, though in a revision of the family it may prove neces- 
sary to establish another genus which shall include also such 
forms as nigrifrons. 
SYNOPSIS OF AMERICAN SPECIES. 
A. Vertex strong, disk flat or concave, margin in front of eyes straight. Ocelli on 
a level with the disk of vertex before the upper margin of eye. 
B. Pronotum short, more than twice broader than long, nearly truncate 
behind, posterior angles obtusely rounding, side margins long, elytra 
without a distinct appendix— light colored species with brown mark- 
ings, larvae light, with four brown stripes. 
c. Elytra moderately long, with two outer apical veinlets strongly 
reflexed to the costa, the next one meeting the costa at nearly 
right angles, all three white, dark margined. 
d. Pronotum four-lined, lines sometimes coalescing, black. 
e. Vertex longitudinally lined or else spotted, ground 
color, yellow; front, narrow hilineatus. 
ee. Vertex transversely lined before the eyes, gen- 
eral color white, front broad, inflated albidus. 
dd. Pronotum cinereus, never distinctly dark-lined. 
e. Third apical cell larger than anal one, face dark 
above, light below; species four mm or more long, 
f. Face light or fuscous above, shading out 
below, no sharp line of demarkation, cla- 
val veins not uniting, vertex short, nearly 
right angled, male genitalia inflated, plates 
roundingly pointed; species nearly unicol- 
orous above, except a broad spot in third 
apical cell inflatus. 
if. Face black above, white below, line of de- 
markation sharp, vertex, long, acutely 
pointed, dark markings above, sharp, veins 
on clavus coalescing through the middle 
third, male plates long, acutely, slightly 
concavely pointed . .reflexus. 
ee. Third apical cell smaller, or only equaling anal 
one, face usually entirely dark; species less than 
four mm. long. 
