1946] New Neotropical Species of Chrysops 9 
yellow of 1st and 2nd tergites slightly grey pollinose, the 1st on 
each side with a prominent yellowish pollinose spot; all tergites 
with a few, scattered, short white hairs. 
Length (not including antennae), 5 mm.; of wing, 5.8 to 
6 mm. 
Colombia: Veneral, Rio Yurumangui, Dept. Valle del Cauca, 
March 25, 1943 (Santiago Renjifo Salcedo Collector); holo- 
type and 1 paratype at M.C.Z. (No. 27435). 
Chrysops weberi, new species (Figs. 7-8) 
Female. — Small, related to C. latitibialis Krober and C. 
renjifoi. 
Frons about as wide as high, mostly yellow pollinose and with 
a few erect black hairs; ocellar area very little raised, exten- 
sively denuded, but not extended downward, shiny black with 
yellowish-brown occipital edge; frontal callus large, strongly 
swollen, yellowish-brown, barely separated from the eyes. 
Fronto-clypeus shiny honey-yellow, except for the grey pol- 
linose narrow inner orbits and upper half of cheeks; facial pits 
yellow; upper lateral areas (above the pits) flattened convex, 
not conical. Antennae yellowish-brown, paler on segment 1; 
terminal annuli of segment 3 somewhat more infuscated; very 
slender, much longer than fore femora; segment 1 scarcely 
longer than 2; 3 about one and one-half times the length of 1, 
its basal portion very little swollen, but decidedly thicker than 
1; 1 and 2 cylindrical, not swollen, about equally thick both 
from above and in profile. Palpi yellowish-brown. Thorax 
black; dorsum with a median pair of broad, continuous, yellow 
pollinose spots between scutellum and wing and on antealar 
callosity. Scutellum black, broadly dirty-yellowish along hind 
and lateral margins. Pleura with a number of disconnected yel- 
low pollinose spots, not definitely forming stripes. Legs: coxae 
and tibiae strongly infuscated to blackish; femora and tarsi 
dirty-yellowish to brownish-yellow, the hind tarsi paler; all 
tibiae flattened and moderately widened. Wings marked almost 
exactly as in C. renjifoi , the differences being too slight to jus- 
tify a figure; the clearer, subhyaline spot near the hind margin 
of the cross-band is restricted to the middle of the 5 th posterior 
cell; anal cell mostly hyaline. Halteres yellowish-brown. Ab- 
domen: 1st tergite yellowish with a black apical margin; 2d 
