MONOGRAPH OF THE NORTH AMERICAN PROCTOTKYPID.E. 185 



Thorax with two iini)ressed hues sul)ol)soletc posteriorly; scutclluiu con- 

 vex, separated from the niesonotuni by a transverse I4iie; inetascutel- 

 hull armed with a small a(;iite tooth. Wings hyaliue, ciliated. Legs 

 pale brownish-yellow, the coxa? dusky basally. Abdomen longer than 

 the head and thorax together, narrowed basally iiit(> a petiole and in- 

 serted far up on the metathorax behind the postscutellnm, black and 

 polished. 



Habitat. — Arlington, Ya. 



Type in Coll. Aslimead. 



Described from a single specimen. 



The insect described by me, in the beginning of my studies on this 

 family, under the name X. ri(bicola. is a S Pteromalid belonging to a 

 genus unknown to me. 



PROSACANTHA Nees. 



Mon., II, p. 294 (1«34); Farster. Hyni. Stud., ii, p. 10:5 (ISnfi). 



(P. louijicorulN Nees.) 



Head transverse, the occiput slightly emarginated and delicately 

 margined; ocelli 3, in a triangle, rather close together, the lateral 

 very distant from the margin of the eye; eyes oval, pubescent. 



Antennai inserted on a clypeal ])rominence, 12-jointed, in 9 termina- 

 ting in a long, fusiform, (J-Joiiited club; the fnniclar joints thicker than 

 the pedicel, the first two joints longer than wide; in $ long, filiform, 

 the joints long, cylindrical, the third angulated or emarginated from 

 near the middle towards the base. 



Maxillary ])alpi 3 jointed. 



Mandibles curved, bidentate at tips, the teeth in the left mandible 

 equal, in the right with the outer tooth the longer. 



Thorax ovoid, the jnothorax scarcely visible from above, narrowed 

 into a slight neck anteriorly; mesonotum broader than long, without 

 furrows, seldom occasionally with indications of furrows posteriorly. 

 Seutellum large, semicircular, sulx-onvex; metathorax armed with a 

 large sharp spine or thorn; metathorax very short, the posterior angles 

 usually acute or spined. 



Front wings pubescent, ciliated, with a very long marginal vein that 

 ends at two-thirds the length of the wing and is <) or 7 times longer 

 than the short stigmal vein, the postmarginal never developed. 



Abdomen long-oval, depressed, ^longer than the head and thorax 

 together, inserted high up on the metathorax, the first segment jietio- 

 liform, much longer than wide, fiuted or striated, the third segment 

 always large and occupying more than half the rest of the abdomen, 

 either smooth or striated, the following segments very short. 



Legs long, slender, iiubescent; the femora not especially thick; the 

 tibial spurs weak; the tarsi long, slender, cylindrical, claws simple. 



A genus most frecpiently confused with Tclea.s, but easily separated 

 by the much slenderer hind legs and the weaker tibial spurs. 



