8 PROCEEDINGS OF THE NATIONAL MUSEUM vol.68- 



and two in front of supra-alar; intradorsocentral setiilae in about 12 

 series; both sternopleurals strong; mesopleura with a few short 

 bristles besides the usual long one; scutellum flat above, bristles 

 equal; prosternum haired. Abdomen stout. Fore femur without 

 anteroventral comb; mid femur with a series of short stout bristles 

 on apical half of anterior surface, and one at apex on posterior sur- 

 face ; mid tibiae unarmed posteriorly. Inner cross vein at about one 

 third from base of discal cell; last section of vein 4 about twice as 

 long as preceding section. 



Length, 6 mm. 



Type. — Cacao Trece Aguas, Alta Vera Paz, Guatemala (Barber 

 and Schwartz). Cat. No. 28443, U.S.N.M. 



DRYOMYZOIDES, new genus 



Generic characters. — Ocellar bristles minute, postverticals and or- 

 bitals long, anterior orbitals farther from eye than posterior pair. 

 Intra-alar present; anterior sternopleural minute. First and third 

 wing veins setulose above, the former apically, the latter basally to 

 beyond inner cross vein. 



Genotype. — Dryomyzoides advena.. new species. 



DRYOMYZOIDES ADVENA, new species 



Male and female. — Tawniy yellow^, shining. Face white dusted on 

 sides; ocellar spot dark. Fore tarsi from before apex of basal seg- 

 ment, mid and hind pairs with apical two segments, blackish. Wings 

 clear, both cross veins, and to a lesser extent the apices of third and 

 fourth veins, slightly clouded. 



Orbits not differentiated ; surface of f rons with some minute hairs ; 

 arista pubescent ; lower margin of back of head with two long down- 

 wardly directed bristles on each side ; eye higher than long. Thorax 

 with three pairs of strong dorsocentrals, a strong pair of prescutellar 

 acrostichals, and about 10 series of intradorsocentral setulae; scutel- 

 lum flat above, transverse between the apical bristles; prosternum 

 bare; propleural bristle minute. Bristles on apices of abdominal 

 tergites strong; hypopygium of male small; genitalia of female with- 

 out thorns. Fore femur without the anteroventral comb; mid tibia 

 without distinct posterior median bristles. First posterior cell of 

 wing slightly narrowed apically; the three sections of fourth vein 

 subequal in length; sixth vein rather long and distinct, extending 

 almost to margin of wing; outer cross vein at not more than half its 

 own length from apex of fifth vein. 



Length, 8-9 mm. 



Type. — Female, Alta Boa Vista, Rio de Janeiro, Brazil, August 9, 

 1915 (P. G. Russell). Allotype and one female paratype mounted 



