Dec, I9I2.] Alexander: Revision of Brachypremna. 231 



largely pale brown ; cell i?, with the extreme cephalic margin pale yellow, run- 

 ning down and ending at a drop in the end of cell R3 ; cell i?, brown, with the 

 caudal margin sub-hyaline; end of cell R^ dark with the yellowish spot above 

 described ; R5 dark at tip with a hyaline drop in the outer caudal angle ; cell M^ 

 almost hyaline ; veins with narrow brown seams ; stigma usually with a large 

 sub-hyaline spot in under r, sometimes small or absent. Venation (see Fig. d) : 

 Rg rather long, beyond the arcuation longer than M^., between cross-veins r-m 

 and m ; basal deflection of Cui beyond the fork of M. 



Abdomen : tergum brown, extreme bases of the segments, pale yellowish ; 

 sternum light brownish-yellow with a distinct elongate-ovate black spot in the 

 middle of each segment. 



(^, wing, 21 mm. Fore femur, 12.7 mm.; fore tibia, 14 mm. 



2$, length, 1 7.4-1 7.9 mm.; wing, 1 8-1 8.8 mm.; fore leg, femur, 11. 3-1 1.6 

 mm.; tibia, 13-14. 5 mm.; hing leg, femur, 13. 2-13. 8 mm.; tibia, 13. 6-14. 9 mm. 



Distribution. — Dutch Guiana: Cigi Makoe (H. Polak), Paramaribo 

 (Miss Mayo). Brazil: Igarape-Assu, State of Para (Parish), Rio 

 Blanco (H. H. Smith). 



B. brcvivcntris may be readily distinguished by its dark femoral 

 and tibial tips and pale basal tibial ring. 



Brachypremna williamsoni, new species. 



Tip of femur dark ; base and tip of tibia abruptly light colored ; wings tinged 

 with darker. 



i^(^, length, 11.3-15.7 mm.; wing, 14. 8-19. 3 mm. Fore leg, femur, 10 mm.; 

 tibia, 1 1.4 mm. (paratype No. i). 



Head : rostrum brown ; palpi, basal segment mostly black, second yellow at 

 extreme base and tip, remaining segments brownish-black. Antennae, basal 

 segments, pale brown ; second, light yellow ; flagellar segments with the base 

 brown, tip yellowish, the brown increasing on the outer segments. Front brown ; 

 vertex and occiput light brown, brighter colored adjoining the eye. 



Thorax : rather similar to breviventris, the long intermediate brown stripes 

 quite indistinct ; post-notum with the median brown stripe divided by a pale 

 median line. Pleurae without distinct brown spots. Halteres : base of stem pale, 

 thence gradually darkening to the brown knob. I.egs : coxae grayish-yellow, in- 

 distinctly spotted with brown ; femora brown, not darkened at the tip as in 

 breviventris ; tibia dark brown, a narrow ring at base and tip, pale yellowish- 

 white, tarsi brown, lighter colored toward the tip. 



Wings: conspicuously tinged with darker; costal cells brown; cell R2 with 

 a brown cloud in cephalic portion and a hyaline droplet near outer end; R^ dark 

 at outer end with a sub-apical hyaline spot ; R^ similar with a conspicuous 

 rounded drop; M^, cephalic margin of tip brown, caudal margin of tip with a 

 hyaline drop; cell M^ dark, not hyaline, as in breviventris ; veins with narrow 

 seams of darker brown ; stigma brown, a pale spot in it just below cross-vein r ; 

 (in the type (^, stigma clear brown). Venation (see Fig. e) : Rg beyond 



