214 FAMILY VI. — COREIDiE. 



is scarcely wider than head, their edges nodulate or bluntly 

 toothed ; scutellum small, triangular, nearly equilateral, its tip 

 acute ; corium with hind margin very long, oblique, strongly 

 sinuate, its outer angle acute; membrane slightly surpassing 

 tip of abdomen, its veins numerous, mostly forked ; connexivum 

 usually narrowly exposed ; middle and hind coxae well sepa- 

 rated ; hind tibiae with large flattened dilations, the outer ones 

 the longest and widest ; osteolar opening large, with a short, 

 curved exterior auricle. 



Stal (1870, 149) recognized 23 species of the genus, mostly 

 from Tropical America. Van Duzee (1917, 85) lists six from 

 the United States, one of which is a synonym. Four of the 

 remaining five occur in the eastern states. 



KEY TO EASTERN SPECIES OF ACANTHOCEPHALA. 



a. Humeri of pronotum broadly expanded and extending upward and 

 outward much beyond basal margin of abdomen, thus causing the 

 upper basal part of disk of pronotum to appear concave; outer 

 dilation of hind tibiae broad to almost the tip; length, 28 or more 

 mm. 152. declivis. 



au. Humeri of pronotum but little expanded, not projected outward and 

 upward, the disk therefore not appearing concave; outer dilation 

 of hind tibia? not wide at or near the apex. 

 b. Dilation of hind tibia? extending nearly or quite to apex of tibiae; 

 size larger, length, 23 or more mm. 

 c. Pronotum with numerous small tubercles ; antennae reddish-brown 

 throughout; hind femora of male much swollen, distinctly 

 curved, the median tooth beneath long, stout, curved; outer dila- 

 tion of hind tibiae of male without distinct scallops. 



153. FEMORATA. 



cc. Pronotum granulated, without tubercles; joints 1 — 3 of antennae 



brown, apical one reddish; hind femora of male slender, straight 



or nearly so, its median tooth not enlarged ; outer dilation of 



male hind tibiae with distinct scallops. 154. confraterna. 



bb. Dilation of hind tibiae reaching little more than two-thirds the 



length of tibiae, deeply scalloped in both sexes; apical joint of 



antennae paler than the others; length, 20 — 22 mm. 



155. terminalis. 



152 (237). Acanthocephala declivis (Say), 1832, 10; I, 305, 327. 



Elongate-oval, very large for the genus. Dark brown, above evenly 

 and rather thickly clothed with fine appressed yellowish hairs, beneath 

 densely clothed with whitish ones; antennae reddish-brown, the apical 

 joint greenish-yellow; legs reddish-brown, the hind femora darker; tip 

 of scutellum and incisures of connexivum yellow. Head across the eyes 

 slightly wider than apex of pronotum; antennae slender, basal joint but 

 feebly curved, two and a half times as long as head, third joint two- 



