852 
C. H. TYLKK T0WNSP:NI). 
sliort, not as long as higlit of head, Hesliy, labella well developed ; 
palpi snb-filifonn, very slightly thickened toward the tip. Antennie 
shorter than the face (about two-thirds its length) ; first joint short, 
second somewhat elongate, third less than twice the length of the 
second ; arista bare, short, somewhat thickened, 8-jointed, genicnlate, 
the second joint nuicli elongate ; inacrochajde of scntellum and ab- 
domen as in Slphoplagia, the longest pair on the scntellum reaching 
almost to the middle of the third abdominal segment. Abdomen of 
$ nearly oval, more pointed behind than in Siphoplagia ; of % 
much narrower, almost conical ; frst abdominal segment abbreviated. 
\Vi ngs without costal spine; posterior and apical cros.s-veins very 
obli(|ue, parallel with the hind border of the wing; posterior cros.s- 
vein arising much before the small cross-vein, terminating in the 
middle between the latter and the bend of the fourth vein, which 
hears a very lon_g stuni|) of a vein ; apical cell almost closed in the 
margin, ending very much before the tip of the wing; third vein 
spined very nearly its whole length, frst spined all the way to costa. 
Tv])e, G. plagioldes n. sp. 
This genus differs from Plagia principally in the geniculate arista. 
(lioiiioclliBtii n. sp. 9 silvery. Eyes dark hr own ; 
front about five-nintlis the width of head, face of equal width ; front, face and 
cheeks silvery white; frontal vitta hrownish cinereous, split posteriorly enclosing 
the ocellar ai-ea ; two pairs of ocellar bristles intermixed with black hair, the 
pair behind the ocelli directed backward and a little outward, the longer curved 
))air in front directed outward and a little forward; first and second antennal 
joints and base of third, particularly the posterior hasal ])ortion, reddish yellow; 
arista and remainder of third joint black ; second joint with a hlac^k bristle on 
its anterior surface, third joint a little more than one and one-half times as long 
as the second ; proboscis brownish ; palpi yellow, with scattered hairs and three 
black bristles on under surface near tij); occiput silvery, clothed with gray hair, 
with a fringe of black bristles on the orbital margin. Thorax and scntellum 
silvery, clothed with short bristly hairs and posteriorly inclined macrochsetse ; 
two narrow, median, posteriorly divergent, black vitte begin at anterior border 
of thorax and become obsolete a little beyond the suture, a median vitta arising 
between them at the suture ; a wide, less well defined vitta on each side, inter- 
rupted at the transverse suture ; humeri and pleurte silvery, latter with poste- 
riorly directed bristles on hind border, excejit two lowest, the U])per one of which 
is directed outward and upward, the lower one outward, downward and forward : 
some bristles below humeri directed outward, forward and u])ward. Abdomen 
covered with short, black, dejiressed bristles, first segment black ; basal half of 
second, third and fourth segments sil very pollinose, posterior half lilack, shining; 
first segment with a lateral macrochaeta on margin; second with a lateral and a 
median pair on margin ; third segment with eight marginal macrochaetw, the 
outer ones on the ventral surface and apparently still others on venter; fourth 
segment with four marginal macrochtetic above and several intermixed with 
