540 



UNITED STATES NATIONAL MTJSEXJM BULLETIN 2 24 



on the basal third, with some additional, stiff or bristly 

 hairs; the proboscis is directed chiefly forward and 

 slightly downward. Palpus rather long and slender 

 with niunerous, fine hairs and at the apex 5 or 6 slender 

 bristles. The antenna is attached at the upper third of 

 the liead or just above. The first segment is 1% times 

 as long as the second segment ; both segments bear sev- 

 eral, stiff, bristly setae ventrally, and a few, fine hairs 

 dorsally. Third segment elongate oval but narrowed 

 only near the apex ; it is nearly as long as the first an- 

 tennal segment and bears an unusually long, slender 

 style, longer than all 3 segments combined; microseg- 

 ment absent. For most of the length the style is ringed 

 by micronodular, extremely short setae. 



Head, anterior aspect: The face below the antenna 

 is a sixth the head width and expanded at the epistoma. 

 Subepistomal area rather large, oblique, deeply concave, 

 V-shaped and pubescent. The face is apilose ; the gib- 

 bosity bears numerous, long, moderately stout bristles, 

 the more central elements along the epistomal margin 

 are stout and consist of 3 or 4 pairs of dorsal, black 

 bristles; the remaining bristles pale with numerous, 

 slender bristles along the subepistomal lateral margins. 

 Sliddle face bristles extend beyond the apex of the 

 proboscis. Front short, plane and pollinose with 4 

 minute, bristly hairs along the eye margin and a row 

 of 4 additional, slender, bristles or bristly hairs in front 

 of the antenna. Vertex narrow, only moderately exca- 

 vated, with vertical sides and the ocellariimi low; 2 

 pairs of stout, short, proclinate bristles behind the 

 ocelli. Anterior eye facets enlarged. 



Thorax : The thorax is pollinose ; the pile of meso- 

 notum in the male consists of scanty, fine, suberect, 

 bristly hairs with a distinct band of acrostical pile of 

 the same character ; the dorsocentral elements are poorly 

 differentiated, becoming long and fine posteriorly. Pile 

 of female mesonotum considerably shorter and more 

 minute; the posterior dorsocentral elements are some- 

 what more conspicuous. The moderately stout, long, 

 lateral bristles consist of: 2 notopleural, 1 supraalar, 

 1 suprapostalar, 3 or 4 postalar and 1 moderately strong 

 pair of scutellar bristles, with an additional weak, 

 lateral pair. Scutelliun thick, convex, with impressed 

 rim and deep crease; the disc bears some fine, mod- 

 erately long, bristly hairs; propleuron with fine pile 

 ventrally and laterally. The pronotum has 4 pairs of 

 stout, black bristles in the female but in the male later- 

 ally on the side margins of the pronotum there are at 

 least 4 additional, stout, black bristles. Upper poste- 

 rior pronotum with fine pile in both sexes; mesopleuron 

 with a few, fine, stiff hairs doi'sally ; pteropleuron with 

 3 or 4 slender bristles and additional, bristly pile; 

 posthypopleuron with at least 1 stout bristle in both 

 sexes; pteropleural bristles apparently absent in the 

 female, although some fine pile is present dorsally. 

 Metapleuron with an oblique row of 4 stout bristles and 

 some bristly hairs. Lateral slopes of the metanotum 

 strongly creased medially near the bottom with a patch 

 of bristly pile. Lateral and ventral metastemum with 

 bristly pile; postmetacoxal area membranous; pro- 



sternum connected to lateral propleuron by a veiy nar- 

 row, anterior strip of chitin. Tegula pubescent only; 

 posterior basalare with a patch of 8 to 10 slender 

 bristles; anterior basalare with 1 or 2 bristles; squama 

 with a multiple fringe. 



Legs : The anterior and posterior femora are compara- 

 tively slender, the former a little dilated towards the 

 base. Middle femur distinctly but moderately thick- 

 ened through the middle. Dorsal pile of all the femora 

 very fine appressed, short and bristly setate; ventral 

 surfaces of all of the femora with very little pile, the 

 anterior pair with some bristles; medial surface of the 

 hind femur with moderately nmnerous, bristly hairs 

 and some slender bristles. On the hind femur 1 lateral 

 bristle at the basal third, 1 dorsolatei'al at the apical 

 sixth, 1 dorsomedial subapical bristle; medial surface 

 with a slender, basal bristle and with several of the 

 distal elements among the bristly pile, a little stouter 

 or stiffer. Hind tibia with short, setate pile and with 

 1 slender dorsomedial bristle near the middle in both 

 sexes and with a rather stout, dorsolateral bristle quite 

 at the base and an additional bristle beyond the mid- 

 dle; apex with 1 dorsolateral, 1 lateral, 1 ventrolateral, 

 and 2 ventral bristles. Middle femur characteristically 

 with, in the middle of the anterior margin, a dense clus- 

 ter of very stout, spinous, subtuberculate bristles of 

 varying length and becommg a little more numerous 

 anteroventrally ; there are altogether about 25 of these. 

 At the extreme base ventrally is a close-set tuft of 3 

 slender bristles; middle tibia with along the base and 

 middle of the anterior and anteroventral margin a row 

 of numerous, stout, spinelike bristles, 4 on the basal 

 half, and just beyond the middle a tuft of at least 9 

 bristles, with additional bristly hairs. 



Anterior femur with 6 moderately stout, long, ven- 

 tral bristles extending from the middle to the base and 

 at the base with a tuft of 4 additional bristles also long 

 and posteroventrally behind these a row of 12 or more 

 quite short, stout bristles. Anterior tibia with 1 stout, 

 quite basal anterobasal bristle and 3 posterodorsal near 

 the middle. Thei-e are, besides, 6 exceptionally long, 

 basally stout, attenuate, posterior bristles slightly ven- 

 tral in position. Anterior basitarsus shorter than the 

 others, slightly longer than the next two segments. 

 Hind basitarsus longer than the next three segments. 

 All tarsi end in stout, sharp claws, strongly bent at 

 apex, thin, strongly spatulate, long pulvilli and short,, 

 basally stout, empodium, only half as long as the claw. 



Wings : The wings are a little more pointed apically. 

 Marginal cell closed with a short stalk, subcostal cell 

 rather narrow, not expanded ; the second submarginal 

 cell takes origin a short distance beyond the discal cell. 

 First posterior cell a little narrowed in the middle, 

 flared apically to more than twice its middle width; 

 lower vein of the end of the discal cell strongly dravm 

 backward ; base of second posterior cell moderately ex- 

 panded; fourth posterior cell closed and stalked, dis- 

 tally convex, very little convex anteriorly and pos- 

 teriorly. The anal cell is closed and stalked; second 



