32 



PROCEEDINGS OP THE NATIONAL MUSEUM 



scutelluni with onlj' two pairs of laterals, no apical, one pair of 

 discals, besides which there are only ordinary hair^ ; sternopleural 1, 

 1; pteropleural 0; infrasquamal setules a very distinct group of about 

 a dozen, which should be a good character ; propleura densely hairy. 

 Postscutellum absent, the metanotum moderately convex in the middle 

 as in Sa^rcophaffa. Hind calypters remarkably large, yellowish brown 

 in color, the middle lighter. In the specimen the wing3 are divergent 

 and the calypters are flattened so as to be very conspicuous from 

 above, which evidently suggested the name tetrapteva. 



Abdomen black, the hind margins of the first three segments with 

 dark brown pollen which extends forward in the middle to form 

 a rather distinct median stripe, but tow^ard the sides changes an- 

 teriorly to a lighter color so as to leave a pair of pale yellowish 

 pollinose triangles on the anterior })art of the second and third seg- 



FlG. 2. LBPIDODEXIA Tl/TRAPTERA BrAUE AND BERGBNSTAMM. 1. LEFT LATERAL 



VIEW OF GKNITAL SEGMENTS OP MALE. 2. REAR VIEW OF FORCEPS. 3. REAR VIEW 



OF PENIS. 4. Tip of penis. 5. Rear view of accessory plate. Drawn by 

 David G. Hai.l 



ments; fourth segment with pale yelloAv pollen except in the middle 

 on the front part; first and second segments with only lateral 

 macrochaetae, no marginals ; third segment with a marginal pair and 

 a rather dense group of about eight on each side. Fourth segment 

 with a double interrupted marginal row running into a group at 

 each side. These lateral groups are what Brauer and Bergenstamm 

 called fasciculi. Genitalia as figured. 



Legs black, front tibia with a long outer bristle, middle tibia with 

 one on outer front and two on outer hind sides, no flexor; hind 

 tibia with two on outer hind side, two on inner hind and one on 

 outer front sides, the latter at tw^o-thirds the length. None of the 

 tibiae bear villosity. Pulvilli dark brow-n, moderately elongate and 

 considerably widened ; the front tarsus exceeds the tibia by about the 

 last joint. 



Wing subhyaline, the small crossvein infuscated, the fourth vein 

 bent at a slightly acute angle and ending not very far before the 



