MORGAN HEBARD 179 



Type. — &; Venvidio, Sinaloa, Mexico. July 6 to 12, 1918. 

 (J. A. Kuschc.) [Hebard Collection, Type no. 764.] 



Size large for this group of small insects, form slender. Head with \\idth 

 between antennal sockets equal to three-quarters of the interocular width; 

 interocular-ocellar area flattened, shagreenous and with irregular shallow im- 

 pressions, this area forming a sharp rectangle with the dorsal margins of the 

 ocelli; ocelli large, with flat surfaces vertical. Maxillary palpi rather short, en- 

 larged fifth joint nearly as long as combined length of second and third joints, 

 fourth joint two-thirds as long as third. Antennae setaceous, the setae 

 slightly longer and heavier in the proximal, moderately incrassate half. Pro- 

 notum symmetrically trapezoidal, weakly transverse, latero-caudal angles 

 broadly rounded, latero-cephalic angles still more broadly rounded, cephalic 

 and caudal margins transverse, very broadly convex; latero-caudal sulci of 

 disk pronounced, giving the intervening area a greater convexity. Tegraina 

 and wings fully developed, extending slightly beyond cereal apices. Tegmina 

 elongate, subparallel to the broadly rounded apex; discoidal sectors weakly 

 radiating, so that those toward the discoidal vein are parallel to it, those 

 toward the sutural margin weakly oblique to that margin. Wings elongate 

 and rather narrow, radiate field folding fan-wise; numerous (fourteen) costal 

 veins thickened to near bases, unbranched median vein connected with dis- 

 coidal vein by a number of transverse vetnlets, ulnar vein with (two) complete 

 distal and several irregular incomplete proximal branches, intercalated tri- 

 angle obsolete. Dorsal surface of abdomen^^ with eighth tergite narrowly 

 visible except laterad, where it is symmetrically and triangularly produced 

 and folded about the lateral portions of the base of the subgenital plate, dorso- 

 mesad with a low triangular conical projection, the preceding (seventh) 

 tergite narrowly visible laterad and emarginate to the caudal margin of the 

 sixth tergite mesad, which margin, in consequence, is adjacent to the conical 

 projection of the eighth tergite. Supra-anal plate transverse, broadly and 

 roundly triangularly produced between cereal bases with distal portion 

 decurved. Subgenital plate with sinistral margin briefly oblique below sin- 

 istral cercus, then briefly transverse where mesad is situated the sinistral 

 style, beyond in remaining two-thirds broadly and slightly irregularly angu- 

 lato-convcx, with dextral style situated at apex. Styles small, simple, cylin- 

 drical, unarmed; the sinistral shghtly tapering and very weakly decurved, 

 slightly over twice as long as its proximal width; the dextral scarcely tapering, 

 slightly heavier and shorter, but otherwise similar. Limbs slender. Ventro- 

 cei)halic margin of cephaUc femora armed with large but delicate s{)ines 

 proximad, succeeded by a row of minute, piliform spines, terminating distad 

 in two large but delicate spines, the more distal of which is the longer by a 

 third; ventro-caudal margin unarmed except for a single delicate distal spine. 

 Other femora with a dehcate genicular spine and ventral margins armed with 

 a similar distal and one to three other smaller, delicate sjjines, these short on 



-8 As has been our custom, we coimt tlu; ten dorsal alxloniinal segments as 

 foHows; median segment, first to eiglith (ergites, supra-anal ])Iates. 



THAN.S. .\.M. K.NT. SOC, XLVIII. 



