496 



tTNITED STATES NATIONAL MUSEUM BULLETIN 224 



lateral and anterior pile abundant, fine, rather long 

 and appressed ; ventrolateral surface, ventral and ven- 

 tromedial surfaces of the hind femur with moderately 

 abundant, quite fine, nearly erect pile; ventral sur- 

 face of the hind tibia with only fine, short, scattered 

 pile; a brush of setae entirely confined to the medial 

 surface. In the type of genus the hind femur has 

 10 ventrolateral bristles (m the middle of the femur 

 this row swings outward), 5 dorsolateral (the distal 

 subaj)ical element has a dorsal and also dorsomedial 

 counterpart), and the apex with a medial bristle. The 

 hind tibia has 6 stout, dorsomedial bristles, 4 dorso- 

 lateral, and 2 ventrolateral on the outer half. Middle 

 femm- with some fine, long pile dorsally on the basal 

 half, 3 short bristles m the middle posteriorly, and 3 at 

 base anteroventrally, with another at tlie middle. The 

 middle tibia bears 2 anterodorsal and 2 posterodorsal, 

 2 anteroventral, all confined to the distal half, and also 

 4 posteroventral bristles. Anterior femur with a pos- 

 terior dorsal fringe of long, fine pile; anterior tibia 

 with 1 or 2 short, weak, basal anterodorsal, 3 or 4 short, 

 stout posterodoi-sal at the middle and beyond, and 3 

 long, stout, distal posteroventral bristles. All tarsi end 

 in exceptionally slender, long, slightly blunt claws; 

 spatulate pulvilli about two-thirds as long as the claw; 

 and a quite short, basally stout empodimn fi'om a 

 fourth to half the length of the claw. 



Wings: The wings are broad, the marginal cell is 

 closed with a moderately long stalk; the costa and the 

 first vein are greatly thickened and, with the marginal 

 cell, are expanded and strongly rippled in the male ; in 

 the female there is no thickening and no expansion. 

 Subcostal cell is narrow in both sexes ; discal cell quite 

 narrow, the rectangular, anterior crossvein enters the 

 discal cell at the outer third. The fourth posterior cell 

 is convex anteriorly ; second basal cell ends in two veins ; 

 anal cell closed with a short stalk. Both branches of 

 the third vein end distmctly above the wing apex ; first 

 posterior cell quite narrow in the middle, greatly 

 widened distally; lower end vein of the discal cell 

 puUed back toward the base; fourth posterior cell 

 closed with a long stalk; alula large, ambient vein 

 complete. 



Abdomen: The abdomen is not as wide as the 

 mesonotum ; it is elongate, rather strongly tapered, and 

 in the female longer tlian the wing. Pile of abdomen 

 very abundant, exceptionally fine and long on the sides 

 of the first three or four tergites in the male, much 

 shorter and more scanty in the female. The male in 

 some species may have dorsal mats of hair, posteriorly 

 appressed and curving outward along the posterior 

 margin. Female with only short, appressed, setate pile. 

 Lateral corner of the first tergite unusually strongly 

 protuberant and convex, with 4 to 6 bristles, either stout 

 or slender, and other, long hairs. Bristles absent on 

 the remaining tergites in the male; females with weak, 

 posterolateral marginal bristles ; these tend to be con- 

 fined to the first three tergites. Stemites with long, 

 fine pile in the male; scanty, appressed, short pile in 



the female; first sternite apilose. Male with eight 

 tergites, but the eight short and liplike dorsally, 

 slightly longer laterally; seventh seg:nent greatly re- 

 duced medially and only a fourth as long as its lateral 

 length. Posteriorly this segment has a wide crescentic 

 arch of membrane which may form a deep pocket or 

 crease; it is probably related to the upturned position 

 of the epandrium. Female with seven tergites, the 

 eighth tergite forming a subcylindrical ovipositor as 

 long as the sixth and seventh tergites together and 

 strongly convex dorsally, slightly compressed laterally 

 below. The ninth and tenth tergites are short. 



Male terminalia not rotate ; conspicuous and elongate. 

 The superior forceps form the largest elements; they 

 are elongate, and tend to be narrowed near the apex, 

 with 1 or 2 dorsomedial, notched and sometimes a club- 

 shaped, apical process. The moderately long proctiger 

 thrust obliquely upward has a spearlike process arising 

 beneath it. The gonopod is large but not quite half 

 as long as the superior forceps. The eighth sternite 

 forms a very long, shovel-like structure, which extends 

 fully as far as the gonopod, encloses the latter basally 

 and diverges from it only near the apex; this eighth 

 sternite is quite convex ventrally and on the outer half 

 bears a dense, subappressed brush of long, coarse, 

 matted, bristly pile. Superficially these terminalia re- 

 semble Nerax, new genus. The hypandrium is short 

 and completely concealed by the eight sternite. The 

 female terminalia consist of the very long, nearly 

 cylindrical eighth segment and the much shorter, sub- 

 cylindrical ninth segment; the short tenth segment is 

 somewhat more compressed laterally especially on the 

 posteriorly produced ventral component where the ends 

 are tightly apposed. The shining, not pollinose, pos- 

 terior half of the seventh segment might be considered 

 to contribute to the ovipositor. 



Distribution : Neotropical : Lochrrwrhynchus griseus 

 Guerin (1830) ; long iter ebratus Macquart (1849) ; 

 senecifws Wulp (1882). 



Lonchodogonus, new genus 

 Figures 209, 751, 1435, 1444, 2256, 2281, 2373, 2382 

 Type of genus: Lonchodogonus crihratus, new species. 



Large flies with a very prominent, abraptly developed 

 gibbosity on the lowest three-fifths of the face. The 

 head is nearly circular from the anterior aspect. Both 

 branches of the third vein end above the wing apex. 

 The male terminalia have the eighth sternite produced 

 as a basket-like scoop, accentuated by numerous, arch- 

 ing, curved bristles, which form the basket. Female 

 teiTninalia compressed on the eighth segment, conspicu- 

 ously expanded on the ninth and tenth segments. 

 Length 25 mm. 



Head, lateral aspect: The face has a long, rounded 

 gibbosity on the ventral three-fifths; the upper part 

 barely extends beyond the eyes. The eyes are narrowed 

 and angular ventrally. The occiput is prominent and 



