258 DIPTERA 
2. GENUS COLABRIS, NOV. GEN. 
Characters. — Eyes large, subcontiguous beneath the antenna; but the lower facets not 
greatly enlarged; front very short; antennal style wanting. Thorax not tapering toward the front, the 
humeral grooves deep. in front of the scutellum the notum is slightly flattened but is not at all concave, 
scutellum strongly convex, about as large as the metanotum and devoid of bristles; pygidium small, 
closed, not forcipate; ovipositor very long and slender, ensiform. — Front legs raptorial, the front coxze 
as robust as their femora, thelatter weakly setose. Auxiliary vein straight, completely fusing with the 
costa beyond its base, no humeral crossvein, basal half of the pedicel of the second and third veins 
abruptly rudimentary, discal cell fused with the second basal, emitting three simple posterior veins, 
anal crossvein practically wanting, — it is faintly indicated however and is distinctly separated from the 
thickened hind margin — costa not abruptly attenuated beyond the fourth vein but continuing around 
the hind margin. 
Type species : C. rufesceus, nov. sp. The two following species, rufescens and coxalis, are the 
only known representatives. 
Geographical distribution. 
I. C. rufescens, nov. sp. (1). Panama. 
2. C. coxalis, nov. sp. (2). Panama. 
3. GENus CHELIFERA, MACQUART 
A. SuBGENUS CHELIFERA, MACQUART 
Chelifera, Macquart, Mém. Soc. Sc. Lille, 1823, p. 150 (1823); Bigot, Ann. Soc. Ent. France (6), 
Vol. 9, p. 123 (1889); Coquillett, Proc. Ent. Soc. Wash. Vol. 5, p. 247, 263 (1903). 
Hemerodromia of authors, Loew, Wien. Ent. Monatschr. Vol. 8, p. 237-255 (1864); Bigot, Ann. 
Soc. Ent. France (3), Vol. 5, p. 562 (1857); Williston, Trans. Ent. Soc. Lond. Vol. 3, p. 440 
(1896); Bezzi, Ann. Mus. Hungar. Vol. 3, p. 452 (1905); Nova Acta Akad. Naturf. Halle, Vol. 91, 
P- 299 (1909); Lundbeck, Dipt. Dan. Vol. 3, p. 228 (1910). 
Mantipeza, Rondani, Dipt. Ital. Vol. t, p. 148 (1856); Bigot, Ann. Soc. Ent. France (6), Vol. 9, 
p. 124 (1889); Coquillett, Proc. U. S. Nat. Mus. Vol. 18, p. 389, 392 (1895); Williston, Trans. 
Ent. Soc. Lond. Vol. 3, p. 440 (1896); Coquillett, Proc. Ent. Soc. Wash. Vol. 5, p. 252 (1903); 
Proc. U. S. Nat. Mus. Vol. 37, p. 565 (1910). 
(1) Colabris rufescens, nov. sp. — Length 2 2 mm.  Reddish yellow, the head, metanotum and genitalia black, 
à diffused prescutellar spot dark brown, the lower mesopleurze, scutellum and haltereslightbrown. Lower occiput bearing 
the usual densely white pruinose orbital mark, front no longer than the distance between the posterior ocelli, eyes very 
narrowly separated on the face, mouthparts yellow, palpi short; antennze yellow, the third joint ovate, one-half longer than 
broad, with a microscopic style. Thoracic setulz microscopic, the two rows of acrostichals almost contiguous, notum and 
pleurse not pollinose, rather shining. Front coxe but slightly shorter than their femora, of the male inflated, nearly as 
thick as their femora, of the female slender, Abdomen more or less fuscous, ovipositor nearly as long as the abdomen. 
Veins strong, brown, the second third and fourth sections of the costa proportioned 2 : 4 : 3.5, sections of the fifth vein 
proportioned 1:2: 1. 
Three specimens; Alhajuelo, Canal Zone, Panama, collected by August Busck. Type inthe U. S. National Museum. 
(2) Colabris coxalis, nov. sp. (PI. 3, Fig. 27). — Length 22 mm. Same as rufescens, but the front coxze are 
blackish and their hairs are black. Second, third and fourth sections of the costa proportioned 2 : 3 5 : 4. 
Two specimens; Alhajuelo, Panama, March. Type in the U, S. National Museum. 
