NORTH AMERICAN DIPTERA. 
367 
thickened on distal two-thiids, black bristly with some longer bristles on under 
surface; occiput cinereous, densely gray hairy, with a fringe of black hairs on 
orbital margins, very long hairs alternating with very short ones. Thorax sil- 
very-cinereous, hairy and bristly, with four more or less distinct, rather narrow, 
black vittiE ; scutellum a little blackish at base, broadly tipped with tawny 
brown, with a rather small, decussate apical pair of macrochse tie ; just outside 
these a strong pair reaching to base or nearly to middle of third abdominal seg- 
ment; two lateral macrochsetie on each side: humeri and pleui-se silvery-cine- 
reous. Abdomen rather oval, covered with short, thick, black bristles, first seg- 
ment somewhat shortened ; color black, bases of all but first segment broadly 
silvery, fully covering the basal half; sides of second segment more or less red- 
dish ; first segment with a median marginal pair of macrochsetie ; second with 
a median marginal pair, and a lateral marginal one; third with about ten mar- 
ginal macrochaetfe, six of these being on the upper side; anal segment well 
armed with discal and marginal macrochsetie. Legs black, femora silvery, tibiie 
slightly so, femora bristly, tibiae more stronsly so ; claws and pulvilli quite elon- 
gate. Wings a little longer than abdomen, not wide, grayish hyaline, very 
slightly tawny toward base, with costal spine, third vein spined at base ; apical 
cell ending well before the tip of wing, open ; fourth vein bent at an angle, with 
a well defined wrinkle at its bend; hind cross-vein oblique, somewhat crooked, 
nearer to the bend of fourth vein ; tegulae nearly white, halteres brownish. 
Length 6 — 9 mm. ; of wing — 6§ mm. 
I believe that P. appendiculata v. d. Wulp is the same as this spe- 
cies. I refer four S specimens here ; one from So. Florida and three 
from So. Illinois (Robertson). All four, however, show a more or 
less faint rufous tinge on the sides of the second abdominal segment. 
Acroslossa hespericlariiiu Willist. Scudd. Butt. N. E. 1917. 
I have one specimen of this interesting genus and sjiecies from 
Kansas. It agrees perfectly in every particular with Dr. Willistou’s 
descriptions. 
Froiitiiia acroglossoicles u. sp. 'J, (?). — Blackish, cinereous. Head, 
thorax and abdomen broad, of equal width. Eyes light brown, bare; front one- 
third width of head at vertex, wider before, blackish, cinereous on forward por- 
tions ; frontal vitta brown, rather wide, cleft behind on each side of the ocelli ; 
frontal bristles descending but little below base of antennae, the rows widely 
divergent below ; a pair of posteriorly directed bristles at each vertical angle, 
the outer smaller one also directed outward ; next frontal bristle directed poste- 
riorly, rest directed inward, slightly decussate; two orbital bristles; ocellar area 
clothed with black haii-s, with two pairs of bristles, the forward pair longer, 
directed forward and outward; sides of face and fi-ont clothed with fine hairs ; 
sides of face and upper part of cheeks golden polliuose, sides of face wide ; cheeks 
one-third eye-hight, silvery and black hairy below, with a row of bristles on 
lower borders ; face receding, silvery-white, epistoma somewhat prominent, 
facial ridges with a row of bristles extending nearly to base of third antennal 
joint; vibrissse decussate, inserted well above the oral margin ; antennse shorter 
than face, first joint short, dark brown ; second joint considerably longer, light 
