262 THE BLowFruiss or NortH AMERICA 
and 0.32 at lunule, with rather heavy gray pollen, and with some 
scattered short black setae outside frontal row which extend to 
just anterior to foremost frontal bristle; frontal rows of bristles 
extending to about base of second antennal segment and narrowly 
diverging anteriorly as they follow the margin of frontale, each 
row consisting of about eight or nine bristles; inner vertical 
bristle strong, decussate or reclinate; frontoorbital bristles ab- 
sent; vertex subpollinose, black; ocellar triangle black, often 
metallic green; clypeus about twice as long as wide, silvery; 
parafaciale opposite lunule 1.4 in width, as wide below, silvery; 
vibrissae above oral margin by 1.4 and separated by 2.1; proboscis 
9.0 in length; haustellum 0.33 head height; palpus orange, 3.6 in 
length; antennae with bases approximated, brownish black, third 
segment 3.2 times as long as second and reaching four-fifths the 
distance to the vibrissae; arista elongate, black, with long black 
cilia above and below almost to apex; back of head black with — 
greenish overcast and whitish pollen, with three rows of postocu- — 
lar cilia and with abundant medium-length black hair. 
Thorax metallic yellow green, slightly bluish in certain lights, 
rarely purplish, with very thin whitish pollen or shining, and 
without dorsal longitudinal stripes; pleura shining or with a 
trace of whitish pollen; humeral bristles three strong, with a 
weaker fourth anterior to these; propleuron with abundant black 
setae in center; preintraalar bristles three, the foremost usually 
weak, the hindmost bristle placed anterior to suture by 0.5; 
preacrostichal bristles two strong, the hindmost bristle placed 
anterior to suture by 1.5; predorsocentral bristles three strong, 
the hindmost bristle placed anterior to suture by 2.5; sterno- 
pleuron with black setae except on anterior fifth; pteropleuron 
with anterior half brown, posterior half metallic green; proster- 
num laterally with black setae; postalar declivity anteriorly with 
scattered black setae; preparapteron brown, with short fine 
decumbent white pile; hypopleuron setose on posterior half; 
preepaulet black; tympanic pit with tuft of long black setae; 
squamal process brown; postparapteron brown to black; greater 
ampulla black, with short fine decumbent brownish pile; scutellar 
bridge with long black setae; squamopleuron with soft. short 
tawny pile; postacrostichal bristles three strong; mesothoracic 
spiracle and metathoracic spiracle with dark brown hair; halters 
orange brown; scutellum with under surface laterally with fine 
brownish- blacks setae and discal bristles located laterally and pos- 
teriorly; lateral postscutellar plate with black setae. 
Legs black, anterior femur often greenish metallic; anterior 
tibia with one posteroventral bristle near apical third; middle 
