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UNITED STATES NATIONAL MtTSEXJM BULLETIN 2 24 



ing nearly to the base, 2 or 3 of which are slightly 

 longer. Second segment similarly clothed but only on 

 the outer half. Third segment with 3 or 4 dorsal setae. 



Head, anterior aspect : The face below the antenna is 

 about an eighth the head width and expanding greatly 

 below. Subepistomal area rather large, V-shaped, deep, 

 oblique with slanting sides and pubescent. Face pu- 

 bescent, without pile except for 5 or 6 long, slender hairs 

 lying above the triangular patch of midventral bris- 

 tles. This patch contains dorsally 2 and below it 8 

 bristles disposed in 2 rows, followed by a ventral circlet 

 containmg 4 paire of long, stout, pale bristles. Sides 

 of subepistoma with slender bristles. The front is of 

 the nearly same width as the upper face or very slightly 

 wider. The vertex is distinctly convergent; sides of 

 front with a dense patch of appressecl setae. Ocel- 

 larium low with 3 or 4 pairs of appressed setae directed 

 forward and placed behind the ocelli. Vertex deeply 

 excavated with nearly vertical sides. Eye facets en- 

 larged. 



Thorax : The mesonotum and pleuron poUinose. Pile 

 of mesonotum scanty, fine and setate, the acrostical ele- 

 ments more coarse and consisting of 2 to 3 rows with 

 bare, adjacent stripe; the dorsocentral bristles are ex- 

 panded laterally only to the humerus; they become 

 long in the middle of the mesonotum and are quite long 

 posteriorly. Humei-us pilose. Long, stout, lateral 

 bristles are present and consist of 2 notopleural, 1 or 

 2 postsupraalar, 1 suprapostalar, 3 postalar, and 1 pair 

 of scutellar bristles. Scutellum thick, convex, with im- 

 pressed rim and 12 to 15 long, stiff hairs on each side. 

 Pleuron with stiff pile ventrally and a fringe row of 

 weak bristles immediately above the anterior coxa, with 

 long, stiff hairs on the posterodorsal section, 5 or 6 weak 

 bristles on the pronotum. The mesopleuron has only 

 a few, very fine, scattered hairs posteriorly, additional 

 ones on the upper posterior stemopleuron, and 8 to 15 

 long hairs on the upper pteropleuron ; it has a vertical 

 row of 4 long, stout bristles on the posthypopleuron and 

 a similar row of 5 on the metapleuron. Metanotal slopes 

 buUose with a dense patch of long, stiff, upwardly 

 curved pile. Lateral and ventral metastemum with 

 numerous, long, stiff hairs; postmetacoxal area mem- 

 branous, pubescent ; posterior basalare with 2 or 3 dis- 

 tinct bristles and some setae; squama with multiple 

 fringe. Prosternum nan-owly fused laterally. 



Legs : All the femora are stout, the middle and an- 

 terior pairs especially stout. The principal characteris- 

 tic of these legs is the reduced number of bristles and 

 the long, ventral fi'inge of 7 or 8 stout bristles on both 

 anterior and middle femora. Hind femur rather dense- 

 ly appressed setate on all surfaces except medial, and 

 bearing 3 fine, bristly hairs medially at the apex, 1 

 stout bristle dorsomedially, some distance from the 

 apex, 4 lateral bristles, also 3 ventrolateral on the basal 

 half, and at the base ventrally a cluster of 3 quite long 

 and 1 adjacent medial bristle, and 3 other ventral bris- 

 tles near the middle. The hind tibia bears 1 dorsal, 3 

 doreolateral, 2 ventrolateral on the outer half, and a 



dense brush of setae medially beginning near the base ; 

 apex with 1 dorsal, 2 lateral, and 4 ventral bristles. 

 Middle femur with 3 stout anterior, 3 stout ventro- 

 lateral, and 7 ventral bristles. Middle tibia with 2 weak 

 dorsal, 2 anterodorsal, 3 long, slender posterior, and 2 

 exceptionally stout, ventral bristles restricted to the 

 outer half; also there are 6 spinous, ventral bristles. 

 Anterior femur with 8 long, ventral, tuberculate bris- 

 tles; this tibia has 2 weak dorsal, 1 stout posterior at 

 the apical third, and 1 medial brush of setae beginning 

 above the middle; apical circlet of 10 bristles. Tarsi 

 have long pulvilli and empodium, and stout, only mod- 

 erately sharp claws bent rectangularly near the apex. 



Wings: The wings are subhyaline and the apical 

 third and posterior border villose. Marginal cell closed 

 and stalked ; the anterior branch of the third vein ends 

 at wing apex or slightly above; second submarginal 

 cell narrowed in the middle by expansion of the first 

 posterior cell; second posterior cell strongly swollen 

 at base ; fourth posterior cell closed and stalked ; anal 

 cell closed, second basal cell ends in two veins; lower 

 end vein of discal cell drawn backward and nearly 

 parallel with anterior margin of discal cell. The margi- 

 nal cell is rippled basally but not expanded ; alula large, 

 ambient vein complete. 



Abdomen : The abdomen is cylindrical and tapered, as 

 long as the wings; first tergite laterally swollen, weakly 

 ridged. Pile of abdomen abundant, flat appressed and 

 setate; sternal pile scattered, long, erect, with addi- 

 tional, appressed setae. All the tergites have bristles, 

 which become weak beyond the fourth tergite. First 

 tergite laterally with 4 long, stout bristles and other 

 stiff', bristly hairs. Second tergite with 3 or 4 weak 

 bristles submarginally on the posterior margm and ad- 

 ditional, bristly hairs and long, bristly pile in the mid- 

 dle laterally. Third tergite with 4 stout bristles in a 

 similar position and with a sublateral row of scarcely 

 less stout bristles. Fourth tergite with 5 or 6 mod- 

 erately strong, posterior bristles and 8 to 10 lateral 

 bristles. Remaining tergites with weak bristles. Basal 

 sternites with some long, bristly hairs and on the sides 

 of the third sternite a lateral cluster of 10 to 12 stout, 

 long bristles; fourth sternite with a similar, lateral 

 cluster of weaker bristles ; eighth sternite with posterior 

 fringe of about 7 moderately stout bristles. Males with 

 eight tergites, the seventh with deeply creased and inset, 

 posterior margin and reduced length medially ; eighth 

 tergite a fifth as long as the sixth in its medial length, 

 but also longer laterally and likewise •with inset, dorsal 

 posterior rim. Male terminalia quite large and con- 

 spicuous and the superior forceps much longer than 

 other elements, with processes; gonopod short, blunt 

 and convex ; the hyjiandriimi varies from short to quite 

 long, broad and extensive. Proctiger long, broad, flat, 

 protruded and oblique. The female terminalia consist 

 of the exceptionally short, cylindrical eighth segment 

 and much smaller, subcylindrical ninth and tenth seg- 

 ments. In some species all three segments may be en- 

 closed by a screen of long, stout bristles originating on 

 the postmargin of the seventh tergite and sternite. 



