200 
O. KROBER 
4. Drittes Fahlerglied 2-mal so lang als das erste und zweite zusammen. Hinter¬ 
leib 2-mal so lang als Kopf und Rückenschild zusammen, mirabilis Adams. 
— Drittes Fühlerglied SVa-mal so lang als die Basalglieder. Taster keulig, 
braungelt)... .. _ „„ \ B .. „„ _ „„ electa Adams. 
1. Omphrale glabrifrons Meig. 
$ . In der Wiener Coli, ist ein 2 als laevifrons Lw. ausgezeich¬ 
net, das sich von unsern palæarktischen Exemplaren absolut nicht unter¬ 
scheidet. Nord-Amerika. 
2. Omphralefenestralis Meig. Taf. Vili. Fig. 14, 15; Taf. XI. Fig. 65. 
$ 9 . Aus Wiedemann’s Sammlung liegen mir drei Exemplare 
vor. die als 0. pallipes Say ausgezeichnet sind; den typischen Exem¬ 
plaren unserer Region absolut gleich. New York, Pennsylvania. 
3. Omphrale nubilipes Say, s. pag. 204. 
4. Omphrale mirabilis Adams. 
$ : «Black, head and thorax subopaque, abdomen shining, with 
short, white pile; first antennal joint slightly shorter than the second, 
closely applied to it, their separation difficult to see; third joint twice 
as long as the first two together, tapering somewhat from the middle 
apically ; a small spot on humeri, and halteres yellow, abdomen broad 
and long, once and a half as long as the wings, twice as long as the 
head and thorax together, knees and tarsi, except tips of latter, yellow ; 
wings hyaline, veins dark brown, width of the first posterior cell at 
margin of wing is scarcely equal to the length of the small cross-vein. 
Length : 4 mm. One example Bill Williams Fork-Arizona. 
Were it not for the open first posterior cell and short sub-mar¬ 
ginal cell, this species would well be located in Pseudatrichia .» 
5. Omphrale electa Adams. 
cf : «Black, with very short white pile; head and thorax sub¬ 
opaque, abdomen shining, hind margins of segments three, four and 
five white ; lower half of eyes of smaller facets than upper half ; first 
and second joints of antennæ of equal length, third twice and a half 
as long as both together ; in certain ligths third is of a brownish color ; 
palpi linear, yellow at the tip ; knobs of halteres pure white ; knees 
and basal half of tarsi yellowish, all tibiæ in certain lights brownish ; 
wings hyaline, veins brown, width of apex of first posterior cell but 
little less than the length of the small cross-vein. 
5 : Agrees with the male, except the palpi are very much enlar¬ 
ged at apex, clavate, tip brownish yellow, and non of the abdominal 
segments have white posterior borders. Length : 2*5 mm. 
Bill Williams Fork, Arizona.» 
Yon den Arten kommt 0. nubilipes Say auch in Südamerika vor. 
