SYSTEMATIC ACCOUNT. 49 
nocephala, Hypselothyrea, Liomyza, Sigalessa, and Uranucha because it 
seems to me that they can conveniently be placed in a group of their 
own. Specimens of Periscelis that I have seen seem to fit best in the 
Agromyzine. The types of Stenomicra appear to me to be Geomy- 
zine. Curtonotum and Aulacigaster I have included in the Droso- 
philine because they do not fit well anywhere else, and it is now 
customary to put them here. It remains very doubtful whether they 
are really any closer to Drosophila, Stegana, etc., than are some of the 
Geomyzinz (e. g., Diastata, Mumetopia) or Milichiine. 
In general, a small acalypterate fly with plumose arista, convergent 
postverticals, twice-broken costa, rudimentary auxiliary vein, anal cell, 
and vibrissz present, is a drosophiline. Any specimen with all these 
characters may safely be referred here; but every one of these pecul- 
iarities is lacking in some member of the group. The postverticals are 
always convergent if present; but some forms have no postverticals 
at all. The costa is always at least weakened a second time; but the 
humeral weakening is in some cases not an actual break. Vibrissze 
are present in all North American forms, but absent in the exotic 
genera Idiomyia and Apsinota. The anal cell is very often incomplete. 
The auxiliary vein is well developed in Curtonotum, Apsinota, and 
Aulacigaster. The arista is pubescent in several genera, pectinate in 
Titanocheta, and has a single branch in Cladocheta. 
The following subfamilies are the ones most likely to be confused 
with the Drosophiline: Lauxaniine, Milichiine, Agromyzine, Ephy- 
drine, Geomyzinz, Chloropine, and Asteine. These may usually be 
distinguished by the following means, though with a little practise one 
will come to rely fully as much on the general appearance of the speci- 
men, without examining the minute characters, except in rare cases. 
Lauxaniine: Auxiliary vein distinct throughout its course; two orbital bristles. 
Milichiine: Arista never plumose; auxiliary vein usually ending in the costa; discal and 
second basal cells separated; clypeus small; lower orbital bristles convergent. 
Agromyzine: Costa once broken; postverticals divergent. 
Ephydrine: Anal cell and anal vein absent; face convex or flat. 
Geomyzine: Costa once broken; auxiliary vein usually ending in costa; arista seldom 
plumose. 
Chloropine: Costa once broken; anal cell and vein absent; vibrissee absent; arista rarely 
plumose. 
Asteine: Anal cell absent; arista usually not plumose; costa not broken at humeral cross- 
vein. 
GENERA OF DROSOPHILINA. 
The following will serve to characterize the 22 genera here recog- 
nized as belonging to the Drosophiline. I have examined specimens 
of 17 of them. 
1 Aumiary yeindistinet for most or all of its length... 002-2... 2. eee 2 
Auxiliary rudimentary or ending in first vein near its base.............-..-4-. 4 
2. Arista plumose; prescutellars large; mesonotum strongly convex..............- 3 
Arista minutely pubescent; no prescutellars or postverticals; mesonotum not 
SUNG H Ses OIC eres SE ay ete coe ase ART AN UO ove a ecatsinl avaible oh x ate oe ele ie Aulacigaster 
