350 
7. Several minute setulae in front of genal bristle (Pl. XLVI, Fig. 12); 
penultimate section of fourth vein at least as long as, generally longer 
than, ultimate section of fifth (Pl. XLVII, Fig. 1); usually one and some- 
times two long setulae in front of anterior dorsocentral bristle; fore 
EUDIAS ANG. TATEL CVU Winns aie oie ten vacn etree aim ec wie ois toten tanta eve tars slevere major, sp. Dn. 
— No setulae anterior to ema Pristle acta. apeaye ole a) =\cfelvetetnis ainle!o1ofere t-te ete Sefbis 
8: Fore tarsi largely or entirely yellows .< << (0:6 c..s:00 0 «cis kc os « vines sl oleeielennnes 9 
— fore tarsi largely or entirely black...................- Avie seta leic a5 Soe 10 
9. Large species, 2 mm. or over in length; thorax with two faint brown 
vittae; basal abdominal tergite black except along posterior margin, 
second with two small round black spots, third and and fourth each with 
a central black spot on anterior margin...............-ese00- bella Loew 
— Smaller species, less than 2 mm. in length; thorax without distinct vittae; 
basal abdominal tergite bronzy fuscous except laterally, second with 
two large poorly defined bronzy fuscous submedian spots on anterior 
ITLAN SUM: 5 sags csc syes a\cyeyoue isin) eece ace siel atelete rotate Minis elete teacayetaeel aie iietevers simplex Loew 
10. Entire fore metatarsus yellow; genal bristle very short; frontal lunule 
setulose; abdomen marked as in simplex; veins 3 and 4 parallel apically 
ayelaieteY ls ara (atal's aus "ian ee TASe sai are tatahn co caiolantece es laistoy ens epee Mie Eine Ute kaiet stn parallela, sp. 0. 
— At most only the base of fore metatarsus yellow................. Ae 1. 11 
11. Small species, barely over 1 mm. in length; thorax and abdomen lead-gray 
pruinescent; fore tarsi entirely, mid and hind pairs except base of 
metatarsi; blacks cps seprstsstcbasts sctersicieaeeree CHSC pob anaes minor, sp. 0D. 
— Larger species, averaging 2 mm. in length, thorax and abdomen whitish 
gray pruinescent; fore metatarsus yellow at extreme base, the other 
tarsi with at least the basal two segments yellowish..... americana, sp. D. 
DESCRIPTIONS AND ReEcorps oF ILLINOIS SPECIES 
LEUCOPIS PEMPHIGAE, sp. n. 
Male and Female —Black, opaque, densely whitish gray pruinescent, 
Frons slightly rufous anteriorly, but only noticeably so when the surface 
has been wet, in well-preserved specimens densely whitish gray pruines- 
cent; basal two antennal segments yellow, third deep black, slightly gray 
pruinescent; palpi black. Thorax not distinctly vittate, the areas occu- 
pied by the lateral vittae in other species a little darker gray than the re- 
mainder of disc. Abdomen slightly testaceous at apex; hypopygium 
testaceous ; basal tergite with two large, rounded, poorly defined brown- 
ish fuscous spots, third and fourth sometimes with a small linear dark 
spot in center at base, second with two small round fuscous spots. Legs 
testaceous yellow, femora usually darkened on middle. Wings white, 
veins brownish except at bases. Calyptrae white. Halteres cream- 
colored. 
a 
