Dec, I9I2.] Alexander: Revision of Brachypremna. 235 



Hab. Cassapava, Brazil. (Sellow, Coll.) 

 " Type in Berlin Museum." 

 Adapted from Osten Sacken"s original description, /. c, p. 239. 

 Brachypremna unicolor Osten Sacken. 

 1S87. Brachypremna unicolor O. S., Bed. Ent. Zeit., Vol. 31, pt. 2, pp. 239-240. 



igoo. Brachypremna unicolor Hunter, Trans. Am. Ent. Soc, Vol. 26, p. 285. 



1902. Brachypremna unicolor Kertesz, Cat. Dipt., Vol. 2, p. 263. 



Head: rostrum light brown; nasus concolorous, with short hairs; palpi, 

 basal segment, brownish at origin, paler apically ; second segment pale; re- 

 maining segments brown. Antenna, first segment brown; second segment 

 much lighter colored, yellow ; flagellar segments dark brown with the extreme 

 tip yellow, producing an annulated appearance, this coloring becoming obsolete 

 near the end of the flagellum. Front, vertex and occiput light yellowish-brown. 



Thorax : pra:scutum light brown, the anterior portion of the sclerite suf- 

 fused with brownish, concealing the usual stripes; two distinct brown dots on 

 the extreme cephalic margin of the sclerite; on the caudal portion of the 

 sclerite, the dark stripes become distinct; median dark stripe not double; 

 scutum uniformly light brown with suggestions of darker lines ; scutellum and 

 postnotura pale, with a narrow brown median line and with the lateral edges 

 of the sclerite indistinctly brown. Pleura; uniformly pale without distinct darker 

 marks. Halteres long, brown, pale at the base of the stem. Legs : coxae pale, 

 femora light brown passing into dark brown at the tip ; tibia dark brown, the 

 extreme base slightly paler, but not producing a ringed appearance; tarsi 

 slightly lighter brown. 



Wings : almost hyaline ; cell C light yellowish-brown or yellow ; cell ^; 

 tinged with yellow along the costal margin ; cell R, tinged with yellow at the 

 tip ; veins narrowly margined with pale brown ; darker brown clouds at the 

 ends of the radial veins ; stigma very pale brown with a narrow border of 

 darker brow^n. Venation (see Fig. c) : Rg long, beyond the arcuation, about 

 three times as long as A/,,, between cross-veins r-m and »i ; basal deflection 

 of i?„5 none, so that R,.^ is in a line with Rg and /f^ts and R,ti arise directly 

 from the end of the sector ; cross-vein r-m short but distinct, petiole of cell 

 jV, very short; cell ist A/, sub-triangular; fusion of A/3 and Cu, very slight; 

 basal deflection of Cm, at, or before, the fork of M. 



Abdomen : tergum dark brown, the bases and lateral margin of the seg- 

 ments indistinctly paler; sternum pale, with the median spots on the segments 

 very elongate, black, forming an almost continuous line; lateral margins of the 

 sclerites, darker, brownish. 



9, length, 16.S-18.6 mm.; wing, 18.3-20.1 mm. Fore leg, femur, 11.8 mm.; 

 tibia, 13.3 mm. Hind leg, femur, 13. 8-14 mm.; tibia, 15.4-16 mm. 



Distribution. — Island of Cuba, Cayamas (E. A. Schwarz) ; Is- 

 land of Porto Rico (Moritz) Osten Sacken's types; Island of Grenada, 

 Lesser Antilles (Busck.) 



