950 Tue Buowriirs or Norra AmeriGA 
neither of which extend to seutellum, with thin whitish pollen 
which is most apparent in certain lights just behind head on 
dorsum and on pleura; humeral bristles three strong with usually 
one smaller bristle anterior to and between inner and middle 
bristles; hindmost preacrostichal and predorsocentral bristles 
placed 1.0 and 2.2, respectively, before suture; postalar de- 
elivity with only a few weak hairs; metasternum bare. 
Legs as in sericata except middle tibia usually with one an- 
terior bristle near middle (this sometimes absent) and usually 
with but two or three anteroventral bristles toward base; middle 
tibia usually with but one posterodorsal bristle near middle; 
hind tibia usually without anteroventral bristles (if present, re- 
duced in size). 
Wing hyaline, yellowish basally and all veins yellowish; 
basicosta whitish yellow; costal sections 2 to 6 in the proportion 
64:38: 79:31: 7; anterior cross vein slightly basad of middle of 
second section of fourth vein. 
Abdomen usually ecupreous greenish, with whitish pollen in 
certain lights especially on venter; first segment dark, only 
slightly metallic greenish; second with darkened shining mid- 
dorsal longitudinal stripe beginning at anterior margin and 
widening posteriorly, often extending upon anterior portion of 
third segment. Fifth sternite (pl. 24, M) strongly produced pos- 
teriorly and ventrally, giving the abdomen a ventrally-curved 
habitus. 
Genital segments shining black, setose, large, globose, con- 
siderably hidden dorsally by posterior margin of fourth ab- 
dominal segment and ventrally by the elongate arms of fifth 
sternite. Internal anatomical features (pl. 24, J, K and L) as 
illustrated. 
Female. Head height 9.4; eye height 6.8; bueca 0.26 of eye 
beight; length of head at antenna and at vibrissa 5.5; parafaciale 
opposite lunule 1.8 in width; vibrissae set 2.1 apart; head width 
12.0; front at vertex 0.40 of head width, at narrowest (only 
slightly posterior to lunule) 0.39, and at lunule 0.42; front with 
nearly parallel margins or these slightly narrowing anteriorly; 
frontale slightly wider than parafrontale and narrower an- 
teriorly, reddish orange anteriorly and black posteriorly; ver- 
tex cupreous greenish over black or brown; parafaciale and 
parafrontale often considerably yellowish; third segment of 
antenna 2.6 times as long as second. Wing with costal segments 
4 and 5 longer than in sericata. Abdomen with much more con- 
spicuously whitish pollen especially on venter. 
