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UNITED STATES NATIONAL MUSEUM BULLETIN 224 



swelling beginning near the upper part of the head. 

 Pile of occiput scanty on the upper portion or almost 

 completely absent becoming only moderately abundant 

 below and rather short, but long and fine in some 

 species. There are 8 to 12 slender bristles on the upper 

 part of the occiput. Proboscis directed horizontally 

 forward, very robust and strongly swollen towards the 

 base ; the apex is blunt and more or less truncate, with 

 a characteristic row of stout bristles on the dorsal sur- 

 face near or just beyond the middle. The apex also 

 has especially stiff pile, both dorsally, ventrally and 

 at the tip ; the base has only a few, long, fine, bristly 

 hairs on either side. These flies would come under 

 the group in which the proboscis is laterally com- 

 pressed, although this is only evident towards the apex 

 and never to a marked extent. Palpus unusually 

 large, robust, cylindroid and elongate. There is a 

 short, basal segment which is fused at least medially. 

 Whole palpus covered with numerous, bristly hairs 

 which are especially stiff along the dorsal margins, on 

 the apex and beneath it. 



Antenna attached at the upper fifth of the head or 

 higher and ranging from moderate length to somewhat 

 less than moderate length; in Stiphrolamyra comans 

 there is a very long, curved antenna similar to Parac- 

 tenota Engel, and the third antennal segment in this 

 species is 3 to 4 times the combined length of the basal 

 segments. Usually the first antennal segment is twice 

 as long as the second, the second minute and short. 

 The third segment is usually about 1% times as long as 

 the first two and very wide across the middle with apex 

 attenuate with minute, visible spine. In some species 

 this segment may be long oval. First segment with 

 some long, stiff, bristly pile and 1 or 2 long bristles. 



Head, anterior aspect: The face below antenna less 

 than one-third the head width. Subepistomal area 

 moderately large, oblique and concave. The face has 

 abundant, long, rather fine pile on the dorsal half, be- 

 coming longer and more bristly below, with 1 or more 

 rows of long, slender bristles above the epistoma and 

 sometimes with the pile more or less appressed and 

 directed sharply downward. Front quite short, with a 

 band of bristly pile along the eye margins and some 

 additional pile sublaterally. Vertex rather deeply ex- 

 cavated, the ocellarium moderately large, with slanting 

 sides and with 3 or 4 pairs of long, slender bristles or 

 bristly hairs or with a single pair of long, stout bristles. 

 Ocelli reduced. Anterior eye facets enlarged. 



Thorax: The thorax is thinly pollinose, the meso- 

 notum sometimes entirely sinning. Pile of mesonotum 

 generally abundant and fine but flat appressed and 

 sometimes suberect. Acrostical and dorsocentral ele- 

 ments absent; sides of the mesonotum with the follow- 

 ing complement of weak bristles : 2 to 4 notopleural, 3 

 supraalar or with a row of 6 postalar and 4 or 5 bristles 

 on the scutellar margin or with only fine, short, bristly 

 scutellar hairs or with 3 or 4 pairs of slender, moder- 

 ately long bristles. Disc of scutellum with scattered, 

 short pile ; the surface is rather flat but the rim slanting 

 or convex. Propleuron with a tuft of long, stiff pile; 



pronotum without bristles. Mesopleuron with abun- 

 dant, stiff pile on the whole upper half and 2 or 3 

 bristles posteriorly, or in some species with only a few 

 microscopic, fine, short hairs and a single, distinct, 

 posterior bristle. Posthypopleuron with several long, 

 fine hairs; pteropleuron with 2 or 3 hairs; metapleuron 

 with a band of 8 to 10 bristles, with additional bristly 

 hairs. Lateral slopes of the metanotum micropubes- 

 cent only; sides of the metasternum and the ventral 

 metasternum with pile, the large postmetacoxal area 

 membranous; tegula with setae. 



Legs : The femora are distinctly thickened on all pairs, 

 always dorsally; the hind pair has the swelling ac- 

 centuated distally. The legs are comparatively short 

 as compared with Lamyra; the hind femur and its 

 tibia are a little longer than those of the middle pair. 

 The following complement of bristles may be present : 

 on the hind femur 2 weak dorsomedial placed on the 

 outer fourth with below them 2 medial bristles and 

 2 or 3 rather long medial ones on the basal half. There 

 are 2 dorsolateral, one at the outer fifth, 1 just beyond 

 the middle; 3 lateral bristles; and 1 lateral quite close 

 to the apex. The ventral surface has some scattered, 

 moderately long, bristly hairs. Hind tibia with some 

 fine, bristly hairs dorsomedially but with 3 or 4 short, 

 stout bristles dorsolaterally, 2 ventrolateral bristles, 

 and with several bristly hairs ventrally. Middle 

 femur with 5 or 6 bristles posterodorsally, the outer 

 2 doubled, and with 1 moderately stout, anterior bristle 

 on the outer fourth. Middle tibia with 4 short, mod- 

 erately stout, anterodorsal, 4 or 5 very weak and short 

 posterodorsal, 6 longer, stout, posteroventral, 4 fine, 

 slender, ventral bristles, and 2 anteroventral bristles. 

 Anterior femur with 6 or 7 posteroventral bristles and 

 a like number of ventral bristles, chiefly basal. An- 

 terior tibia with 6 anterodorsal, 7 short and weak 

 posterodorsal, 4 longer posteroventral, and 3 or 4 pos- 

 terior bristles. Basitarsi all short and robust, claws 

 slender with very blunt apex; pulvilli long; the em- 

 podium long and bladelike. 



"Wings : The wings are usually quite slender. Mar- 

 ginal cell closed with a long stalk; anterior branch 

 of the third vein is curved backward in the middle; 

 first posterior cell is usually extremely narrow, but of 

 normal width in some species; it is always open; the 

 fourth posterior cell is closed with a long stalk, its end 

 vein varies from nearly adjacent and plane with the 

 upper end vein of the discal cell to being offset by 

 fully the length of the upper discal end vein. Anal cell 

 closed; second basal cell ends in 3 veins; the alula is 

 large, the ambient vein complete. 



Abdomen: The abdomen is robust, at most very 

 slightly narrowed towards the base and only rarely 

 with parallel sides. Males with seven tergites, the 

 seventh tergite is two-thirds as long as the sixth. Fe- 

 males with the eighth tergite as long as the seventh 

 or only half as long, the seventh sometimes also greatly 

 reduced. Pile of the abdomen short, fine and ap- 

 pressed, sides of all of the tergites with distinct bristles 



