504 



tnsriTED STATES NATIONAL MUSEUM BXILLETIN 2 24 



narrowed and moderately excavated; its lateral walls 

 are vertical; the moderately large ocellarimn is low, 

 with vertical walls, and bears behind the ocelli a pair 

 of small, bristly hairs curved forward. The poUinose 

 front bears a single row of short, weak, ocular, marginal 

 bristles. 



Thorax: The thorax is short and rather high, espe- 

 cially the mesonotum, wliich is evenly convex and 

 poUinose with almost no pile even laterally. There are 

 8 fine setae medial to each humerus, an acrostical row 

 of fine setae and fine, short, dorsocentral bristles over 

 the middle which change to 4 longer, stouter elements 

 beliind. Lateral bristles long and stout; there are 2 

 notopleural, 2 supraalar, 2 on the postalar callosity, and 

 1 pair on the scutellar margin. Scutellar disc pollinose, 

 with 3 or 4 setae on each side and a distinct, impi-essed 

 rim. Metanotal callosity pollinose only. Posterodor- 

 sal mesopleuron and the sternopleuron with a tuft of 

 pile. Metapleuron with 5 slender bristles and 4 that are 

 more stout. Hypopleuron with only 1 hair. Pronotum 

 long and flattened. Postmetacoxal area membranous; 

 prosterniun dissociated. 



Legs : All the femora comparatively slender with fine, 

 aj^pressed setae dorsally ; the ventral and posterior sur- 

 faces are ahnost bare. Hind femur with 3 short, lateral 

 bristles on the basal half, 2 ventrolateral on the outer 

 half, and 1 at base; it also has 2 long, ventromedial 

 bristles, 1 at the base, 1 at the middle and 1 pair of 

 bristles dorsally on each side at the subapex, besides 

 an additional, apical medial bristle. Hind tibia with 

 3 dorsolateral bristles and 2 ventrolateral bristles on 

 the discal half. Middle femur with 2 stout anterior 

 bristles on basal and apical third, a ventral pair of 

 bristles on each side near the base and sometimes 2 

 other, quite stout, ventral bristles, 1 at the middle and 

 1 at the outer fourth, besides a posterior bristle at the 

 apex. Middle tibia mostly with short, weak bristles; 

 there are 1 anterior dorsal bristle at the outer fourth, 



1 posterodorsal on the outer half, and 2 or 3 postero- 

 ventral bristles, besides 2 quite stout, ventral bristles 

 on the outer half. Anterior femur with only a bristle at 

 the apex anteriorly and 2 at the base ventrally. The 

 anterior tibia has a small bristle at the base dorsally, 

 3 or 4 minute bristles anterodorsally and distally, 2 

 others posterodorsally ; its only conspicuous bristles are 



2 long, stout elements posteroventrally at the middle 

 and outer fourth. Claws rather slender, bent at apex 

 and sliarp ; the pulvilli are long; the empodiimi is some- 

 what bladelike. 



Wings : The wings are slender, villose on more than 

 the outer third. The marginal cell is comparatively 

 broad, closed with a short stalk, the second submarginal 

 cell is extraordinarily long and slender, the anterior 

 branch of the third vein is straiglit and ends at the wing 

 apex. The lower branch is nearly straight and ends 

 behind the apex. Fourth posterior cell closed and 

 stalked, the anal cell likewise. The third vein forks 

 before the end of the discal cell. The veins closing the 

 second basal cell are fused for a short distance. Alula 

 large ; ambient vein complete. 



Abdomen : The abdomen is rather slender, the first 

 segment, however, is nearly as wide as the mesonotimi 

 and considerably wider than the second. Surface pol- 

 linose with scattered, coarse setae and with along the 

 lateral margin still more sparse, long, slender or bristly 

 hairs which are bristlelike beyond the second segment. 

 Laterally the first segment has only 2 or 3 weak bristles ; 

 there is a tuft of long, erect, slender, bristly hairs on 

 the sides of the first and second segments and near each 

 posterior corner along the posterior margin of segments 

 2 to 5 there are 2 rather stout, comparatively long bris- 

 tles. Males with eight segments, the eighth dorsally 

 less than half as long as the seventh. Females with 

 only four segments not incorporated in the ovipositor. 

 Male terminalia long and compact, the proctiger ex- 

 truded. The superior forceps much narrowed at base, 

 the gonopod is rather small and short, wedged in be- 

 tween the long hypandriiun and superior forceps. Fe- 

 male ovipositor strongly compressed laterally on the 

 rather high fifth and sixth segments, less high on the 

 less compressed seventh segment and the last 3 segments 

 also only a little compressed and also reduced in size, 

 both in width and height. 



Distribution : Ethiopian : Lycoprosopa atrimaculatus 

 Hobby (1934). 



Genus Polyphonius Loew 



FiGTJRES 325, 761, 1510, 1519, 1575, 2176, 2235, 2277 



Polyphonius Loew, Linnaea Entomologica, vol. 3, p. 402, 1848. 

 Type of genus: Polyphonius laevigatus Loew, 1848, by 

 monotjT)y. 



IMedium size flies, at once characterized by the very 

 greatly thickened and swollen middle femur which 

 bears a row of 6 short, stout spines ventrally on the 

 outer third ; the corresponding tibia has a double row 

 of 4 or 5 short spines distally and ventrally. The ab- 

 sence of a distinct style on the elongate, slender third 

 antennal segment should be noted ; this segment bears 

 a short, wide, rather thin microsegment with apical 

 spine. Length 15 mm. 



Head, lateral aspect : The face is short, gently convex 

 on the upper portion and very slightly concave on the 

 lower half ; it is prominent ventrally only through the 

 recession of the eye. The occiput is imusually thick 

 throughout. The eye is posteriorly nearly plane, except 

 on the lower third where it is strongly recessive antero- 

 ventrally. Pile of occiput is very abvmdant, long and 

 rather fine ventrally; it is scanty in the middle but 

 exceptionally abundant dorsally, with a few of the 

 backward elements proclinate; at the middle of the 

 head and continued dorsally are weak bristles which, 

 while longer above, are slender and poorly differenti- 

 ated from the bristly pile. The proboscis is rather 

 stout, subcylindrical, and very slightly swollen ven- 

 trally on the basal half from the lateral aspect ; on the 

 dorsal aspect it is slightly wider basally ; a medial ridge 

 is absent; the apex bears nmnerous, long, stiff hairs 

 including some below ; the lateral margins basally have 



