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UNITED STATES NATIONAL MUSEUM BXJLLETIN 224 



Subepistoraal area large, concave, pubescent, oblique 

 but. well concealed by a dense band of lateral and an- 

 terior pile and bristles. The face is micropubescent 

 with a dense tuft of long, bristly pile originating from 

 the upper ledge of the facial gibbosity. The whole 

 middle of the gibbosity is densely beset with long, 

 coai-se, bristly pile and stout, still longer bristles; 

 across the upper portion below the ledge is a transverse 

 row of 4 stout bristles rather strongly curved down- 

 ward and followed by a still lower row of two. Across 

 the lower margin of the face above the epistoma is a 

 circular row consisting of 3 paii'S of exceptionally stout 

 bristlas; along the sides of the subepistoma are 4 ad- 

 ditional, lateral pairs, somewhat less stout; and in the 

 middle is a pair of long, slender bristles. The addi- 

 tional stiff, long, white pile is unusually abundant and 

 extends down tlie sides of the subepistoma with a con- 

 spicuous tuft at the lower eye comer. Front quite 

 short, pubescent laterally; the sides slightly divergent, 

 again convergent at the vei-tex. Laterally there is 

 abundant, stiff, white pile, with a dense tuft in the lower 

 corners of the front and a lateral row of 5 slender, 

 black bristles. Vertex deeply excavated, with nearly 

 vertical sides ; the ocellarium of medium heiglit carry- 

 ing between the ocelli 2 pairs of slender, black bristles, 

 2 shorter, stiff, pale hairs, 2 others between the pos- 

 terior ocelli; behind the ocelli a patch of 5 or 6 stiff, 

 black and pale hairs and continued along the posterior- 

 ly extended ocellar ridge a vertical row of stiff pale 

 hairs. Anterior eye facets strongly enlarged. 



Thorax : The thorax everywhere pollinose, except that 

 there is a large bare spot on the middle of the meso- 

 pleuron and on most of the stemopleuron. Pile of 

 mesonotum rather abundant but exceptionally fine, 

 though bristly. There is a medial band of irregular 

 acrostical pile ; the dorsocentrals are not clearly differ- 

 entiated anteriorly but become a little longer over the 

 middle of the mesonotmn ; opposite the postalar are 3 

 pairs of slender, moderately long bristles. Humerus 

 with stiff, pale pile. Lateral mesonotum with slender 

 bristles, consisting of 2 to 4 notopleural. 2 postsupra- 

 alar, 1 or 2 postalar bristles. The scutellum with only 

 a dense lateral tuft of upwardly curved, long, stiff, 

 white pile leaving the middle of the margin and also 

 middle and base of the disc bare. Scutellum quite 

 thick and convex, without impressed run. Propleuron 

 with a dense tuft of long, fine pile ; upper margin of the 

 mesopleuron and the posterior half with considerable, 

 long, fuie pile; tlie upper stemopleuron with excep- 

 tionally abundant, long, fine pile ; pteropleuron with a 

 conspicuous, radiating tuft, of fine pile and a large 

 central patch of similar pile on both the posthypo- 

 pleuron and the metapleuron, the latter have some very 

 slender bristles. Sides of metanotum pubescent only ; 

 tegula with 7 or 8 short setae ; posterior basalare with 

 7 or 8 fine, long hairs ; lateral slopes of the metastemum 

 with dense, fine pile; ventral metastemum chitinized 

 and carrying a patch of short pile only; postmeta- 

 coxal area membranous. 



Legs: All the femora are stout, the anterior and 

 middle pair slightly thickened toward the base; the 

 dorsal pile is fine, moderately long, pale and flat ap- 

 pressed, the lateral pile more or less appressed. The 

 anterior femur in addition to the appressed pile has 

 numerous, long, fine hairs dorsally. On the hind femur 

 are stout, long bristles consisting of 2 dorsolateral on 

 the outer fourth, the more distal bristle matched by a 

 dorsomedial element; on the ventrolateral margin 5 

 conspicuous bristles ; and on the basal half 5 or 6 ventral 

 bristles. The hind tibia has 4 to 6 dorsal bristles, 3 

 dorsolateral, 3 longer posteroventral on the outer half ; 

 and both the ventral surface of the hind femur and tibia 

 with a fine, moderately long brush of bristly pile; a 

 brush of setae present only medially ; the ventromedial 

 margin of the hind tibia in the male has a dense row 

 of short microsetae or microspinules, which seem to be 

 absent in the female. Middle femur with 3 stout, 

 anteroventral bristles; there are 3 posteroventral 

 bristles in the middle, 3 at base, 2 posterior at basal 

 third in the middle and 2 at apex. The middle tibia 

 bears long, exceptionally fine pile anteriorly and ven- 

 trally, short appressed pile dorsally and 3 dorsal 

 bristles, 2 posterior, 3 posteroventral, and 3 anteroven- 

 tral. Anterior femur with dense, long, very fine pile 

 and with 6 ventral bristles only; its tibia has 7 rather 

 short dorsal elements, but with 3 exceptionally long, 

 basally stout posteroventral bristles. The anterior 

 basitarsus is as long as the next two segments ; both the 

 anterior and posterior bristles of these tarsi are quite 

 stout and long. Tarsi end in long, slender, sharp claws, 

 quite plane except at the apex where they are bent; 

 long, well developed pulvilli; and slender empodium. 



Wings : The wings are hyaline, villose; the marginal 

 cell closed, the subcostal cell rather narrow, especially 

 in the males. The costa in the males is slightly bent 

 forward just beyond the middle, the marginal cell is 

 distinctly widened, the ripples prominent and wide. 

 In the female the marginal cell is also to some extent 

 widened and is distinctly wider in the middle than the 

 corresponding portion of the submarginal cell behind. 

 The posterior branch of the third vein ends distinctly 

 before the apex of the wing; the second submarginal 

 cell has nearly parallel sides to the apex and no cross- 

 vein or appendiculate vein is present. The second pos- 

 terior cell is not in the least narrowed ; fourth posterior 

 cell closed with a moderately long stalk, its posterior 

 surface nearly plane, its outer surface slightly and its 

 anterior surface quite strongly convex ; the lower vein 

 of the discal cell is pulled backward ; second basal cell 

 ends in two veins which are fused for a short distance 

 beyond ; anal cell closed ; alula large, the ambient vein 

 complete. 



Abdomen : The abdomen is distinctly less wide than 

 the mesonotum, except on the first tergite. The male 

 terminalia rather large, conspicuous and wide, hence 

 the male abdomen is only slightly tapered. In the 

 males eight tergites are present, the sixth is three- 

 fourths as long as the fifth, the seventh and eighth 

 each extremely short dorsally but considerably longer 



