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UNITED STATES NATIONAL MUSEUM BULLETIN 224 



nent ventrally. Occipital pile short, stiff, scanty above 

 and longer below ; it bears a deeply submedial band of 

 long, outwardly curved, slender bristles or bristly hairs. 

 On the upper third of the occiput are 4 quite stout 

 bristles and laterally behind the vertex 3 pairs of un- 

 usually long, stout, erect, straight bristles. The pro- 

 boscis is rather short and stout, quite obtuse at the apex, 

 basally swollen from either aspect and with a low 

 medial ridge; the apex is smooth with a dorsal mat of 

 anteriorly directed pile and along the outer ventral 

 margin there is a fringe of stiff pile restricted to the 

 apical third. The base below has some long, stiff hairs 

 directed downward and at the basal third there are 

 several additional, long hairs more or less appressed. 

 Palpus clearly of two segments; the first segment is 

 short, swollen and rounded with a narrow dorsal fissure ; 

 the second is a little swollen distally and bears a distinct 

 lateral, subapical pore; the palpus bears a number of 

 stiff bristles apically and dorsally and more slender ele- 

 ments below and laterally. 



Antenna attached at the upper sixth of the head and 

 elongate; the first segment is twice as long as the sec- 

 ond, the second barely longer than its apical width. 

 The third segment is quite long and laterally com- 

 pressed; it is as long as the proboscis and not quite 

 three times as long as the first two segments combined. 

 At its apex it bears a narrow, apically rounded, flat- 

 tened, apparent microsegment which is rather short 

 and carries a dorsal recessed notch in which is a dis- 

 tinct spine. Pile of first segment composed of a few, 

 stiff setae dorsally, 2 rather stout, long bristles in the 

 middle ventrally and a number of other long, stiff hairs 

 ventrally and laterally. Second segment with a com- 

 plete subapical circlet of long, stiff setae. 



Head, anterior aspect: The face below the antenna 

 is about one-fourth the head width and has parallel 

 sides; subepistomal area large, elongate, plane, bare 

 and oblique. Face micropubescent with a dense mat 

 of subappressed, stiff, bristly pile beginning beneath 

 the antenna, the more central portion is medially com- 

 posed of rather flattened hair. Above the epistomal 

 margin there is a single row of stout bristles composed 

 of 7 or 8 pairs. Only the upper half of the lateral 

 subepistomal margins bear bristles or pile. The front 

 is quite short, with a few setae along the eye margin ; 

 the front and vertex slightly divergent, the latter mod- 

 erately excavated, the ocellarium large and high and 

 rounded on top with a pair of strong, divergent bristles 

 and 1 or 2 short, weak hairs. Eyes enlarged centrally. 



Thorax : The mesonotum is pollinose ; the pile is fine, 

 abundant, flat appressed and setate. Acrostical and 

 dorsocentral elements are not clearly differentiated but 

 the prescutellar pile is longer but rather strongly ap- 

 pressed. Lateral margins also with longer and ap- 

 pressed, stiff, bristly pile. Humerus with erect pile. 

 The lateral bristles consist of 1 to 3 weak posthumeral, 

 1 long, stout and 1 or 2 weak notopleural, 2 long, strong, 

 supraalar, 3 similar postalar, and 3 pairs of long, stout 

 scutellar bristles. Scutellar disc thick, convex, polli- 

 nose, without crease and with a dense mat of posteriorly 



directed, stiff, appressed pile on the outer half. Pro- 

 pleuron ventrally with numerous, moderately stout 

 bristles and some stiff pile. Pronotum with 5 or 6 weak 

 bristles. Upper mesopleuron with a fringe of long pile. 

 Posterior corner of mesopleuron with 5 or 6 exception- 

 ally stout, long bristles. Sternopleuron with a few 

 fine hairs; posthypopleuron with only short, scattered 

 pile, the metapleuron with a wide, vertical band of 10 

 to 12 very long, stout bristles and bristly pile. Ptero- 

 pleuron with scattered, fine pile. Metanotal slopes 

 micropubescent only; without pile or bristles. Meta- 

 sternal slopes and the metasternum with long pile; 

 postmetacoxal area membranous but distinctly nar- 

 rowed in the middle on each side; prosternum wide 

 laterally and not dissociated; tegula with numerous 

 setae. 



Legs: All of femora are stout; the middle pair is 

 least thickened. Hind femur slightly arcuate below; 

 it bears dorsally 7 or 8 slender, bristly hairs and later- 

 ally 4 sharp, basally stout bristles, with a medial row of 

 8 to 10 slender bristles but none at the apex. The pile 

 is short, suberect and setate, more strongly matted and 

 appressed laterally and dorsally toward the apex. 

 Ventrally there are only sparse, moderately short, fine, 

 scattered hairs; the corresponding ventral fringe of the 

 tibia is similar and scanty. Tibia rather thickened dis- 

 tally with very little pile and bearing 4 or 5 very 

 slender dorsomedial, 3 tuberculate dorsal, and 5 or 6 

 tuberculate lateral bristles, the latter moderately stout. 

 At the apex narrowly below there is a dense tuft of 

 moderately long, appressed pile. The first 3 tarsal seg- 

 ments have similar mat. Medial apex of this tibia with 

 5 bristles. Middle femur with a stout, subapical pos- 

 terior, a weaker bristle before and after it and also near 

 it a moderately stout anterior bristle placed at the 

 apical third. It has a few, fine, long hairs ventrally. 

 Middle tibia with 5 short dorsal, 2 quite long, stout and 

 2 rather fine, short anterior bristles and 7 moderately 

 stout posterior bristles, besides 7 long, stout ventral ele- 

 ments. Anterior femur and tibia similar but no 

 femoral bristles present. The tibial bristles are similar, 

 the long anterior elements absent, the ventral bristles 

 fewer and weaker. Tarsi end in large, spatulate pul- 

 villi, stout empodium, and quite slender claws. 



Wings: Marginal cell closed with a long stalk; the 

 anterior branch of the third vein is sinuous, ending 

 well above wing apex; the posterior branch ends far 

 behind. First posterior cell slightly narrowed api- 

 cally; fourth posterior cell closed and stalked; lower 

 end vein of discal cell pulled backward, nearly parallel 

 with the wing margin. Anal cell closed and stalked; 

 second basal cell ends in 3 veins ; alula large ; ambient 

 vein complete. 



Abdomen: The abdomen is moderately robust but 

 not as wide as the mesonotum, the sides parallel. Males 

 with 6 tei'gites and a short, liplike seventh. The pile 

 is fine, and appressed and rather matted along the pos- 

 terior margins. First tergite with 2 or 3 stout bristles ; 

 second with 2 distinct, stout bristles laterally; third 

 and fourth with 2 or 3 and none upon the fifth and 



