ART. 10 TROPICAL AMERICAlSr DIPTERA — VAIST DUZEE 57 



All coxae, femora, apical third of posterior tibiae, the fore and 

 middle tarsi from the tip of first joint and the whole of hind tarsi 

 black; tips of fore femora and all tibiae yellow; trochanters yellow; 

 femora with short hair, no longer ones below; fore tibiae without 

 bristles below; middle tibiae with three bristles on lower anterior 

 surface; posterior tibiae with rather long hair below and numerous 

 large bristles above; posterior basitarsi with a large bristle near the 

 base below, which is not erect, and with spurs at the tips of the 

 joints; joints of fore tarsi as 35-11-8-8-10; of middle ones as 4G-25- 

 21-12-13; joints of posterior ones as 40-40-30-18-lG. Calypters 

 black with rather long black cilia, which are inclined to cluster into 

 one mass. Halteres yellow. 



Wings tinged with brown, darkest along the veins; costa much 

 swollen opposite the middle of first vein and a little thickened oppo- 

 site the base of third vein; third vein nearly straight, but very 

 slightly arched ; last section of fourth vein bent at its middle, beyond 

 this bend it is arched so as to approach third at tip, reaching the 

 wing margin some distance before the apex of the wing; cross vein 

 22, last section of fifth vein thirty-one fiftieths of a millimeter long. 



Described from one male, taken by J. M. Aldrich, May 2o, 1926, 

 at the head of the Polochic River, Alta Vera Paz, Guatemala. 



Type.— C2ii. No. 41066, U.S.N.M. 



Genus SARCIONUS Aldrich 



Sarcionus Aldrich, Biologia, Dipt., vol. 1, 1902, p. 341 ; Kansas Univ. Sci. 

 Bull., vol. 1, 1902, p. 47 ; Trans. Amer. Ent. Soc, vol. 30, 1904, p. 273. 



SARCIONUS MACULATUS, new species 



Mais. — Length 3 mm. Face moderately wide, silvery white, not 

 reaching the lower margin of the eyes; front blue with brownish 

 pollen ; palpi and proboscis brow^n ; antennae yellow, third joint a^ ery 

 small, shorter than wide, the arista dorsal, broken in the male but 

 still having several long hairs, in the female long plumose; lateral 

 and inferior orbital cilia j-ellowish. 



Thorax and abdomen dark green, not very shining; thorax with an 

 indistinct coppery vitta; the spot of white pollen at the suture small. 

 Hypopygium black with the lower surface yellowish, its petiole long 

 and quite slender; the lamellae oval, moderately large, whitish with 

 a large, dark brown, apical spot; between the lamellae are small 

 yellow inner appendages and basally from these are black, hooklike 

 appendages; the central organ is reddish yellow and curved. 



Fore coxae wholly yellow with small black hairs and several black 

 bristles; middle and hind coxae black; all femora and tibiae yellow; 

 tibiae without bristles below; hairs on all femora short, black, no 

 longer ones below; fore tarsi yellow with the extreme tips of the 



