250 ENTOMOLOGICAL NEWS. [June, *14 
Gastrops willistoni n. sp. 
Shining to polished black, sparingly brown and gray pruinose; an- 
tennae except apex, clypeus, proboscis, tibiae, tarsi and wing veins, 
tawny; halteres, knobs black; wings yellowish-brown, immaculate. Nar- 
row facial orbits densely pruinose; mesonotum subopake with two com- 
plete median vittae sometimes more or less coalescing, another laterad 
interrupted at suture and extending anteriorly along lateral margin to 
humeral angle, grayish; abdomen bluish-black with a semi-lateral pol- 
ished bronze spot on segment 4. 
Front depressed in middle, with two orbitals. Face two-thirds as 
wide as vertex, I.5.times as long as wide; tuberosity above middle; 
lower slightly retreating part hardly as high as cheeks; five facial bris- 
tles with second from uppermost the longest and opposite middle of 
tuberosity. Clypeus distinct. Cheeks one-half of the height of head, 
with strong bristle. Third antennal joint twice as long as broad; arista 
with 12-14 hairs. i 
Mesonotal bristles strong, normal, scutellum flat, broadly truncate, 
with two elongate conical or cylindrical apical tubercles, each bearing 
long bristles; lateral bristles distinct. 
Abdomen densely scrobiculate; segment 3 1.5 times as long as 2 and 
equalling 4; apical margins of all smooth. Legs clothed with long hairs, 
Hind tibiae more or less polished, swollen and flattened apically. Sec- 
ond costal section twice as long as third; vein 3 sinuate so that first 
posterior cell is narrowed apically. Length 4.0 mm. 
Holotype—é Chapada, Brazil. (H. H. Smith). In the 
collection at Academy of Natural Sciences, Philadelphia, No. 
6066. Possessed through the kindness of Prof. S. W. Willis- 
ton, the author of this genus, after whom I have the pleasure 
of naming this large and well marked species. 
Paratype—1 2, Bartica, British Guiana. 
Allied to niger Will. in its immaculate wings with sinuate 
second vein, but the vittate, subopake mesonotum, the flat 
bituberculate scutellum and larger size will separate this spe- 
cies. 
EXPLANATION OF PLATE X. 
Fig. 1. Philygria basalis, wing. 
Fig. 2. Philygria calverti, wing. 
Fig. 3. Cerometopum mosilloides, head in profile. 
Fig. 4. Psilephydra nemorosa, head in profile. 
Fig. 5. Planinasus ambiguus, head in full. 
Fig. 6. Planinasus ambiguus, head in profile. 
Fig. 7. Planinasus ambiguus, right antenna. 
