SOUTH AMERICAN DIPTERA. 281 



ish. Frontal triangle shining black, with black pile. Mesonotum with opaque 

 black bands, the anterior margin and presutural band ashy, the posterior band 

 moderately shining bluish ; the post-alar callosities, the hind margin of the 

 mesonotum, and the scutellum, except a small yellow spot at the tip, densely 

 covered with short, deep black, velvety pile, wholly concealing the ground upon 

 which it is inserted. Abdomen : tirst segment black ; second segment light yel- 

 low with a median black stripe not quite reaching the hind margin; third seg- 

 ment yellow with a median stripe, as though a interrupted continuation of that 

 on the second, connected with the narrow, sometimes partly obsolete band before 

 the yellow hind margin, brown or blackish; fourth segment shining, somewhat 

 metallic, black, with a median spot in front and a narrow band before the yel- 

 low hind margin, opaque black ; in shape the segment is nearly square and iat- 

 tened, cylindrical ; hypopygium .shining metallescent black. Venter, except the 

 fourth segment almost wholly light yellow. Legs black ; the base of the tibife 

 and tar.si reddish, the hind femora chiefly dark red ; hind tarsi with fulvous pu- 

 bescence below; hind femora much thickened. Wings largely tinged with 

 brownish, especially along the stouter veins. 



Five specimens, Chapada, Corumba and Rio de Janeiro. 



72. Eristalis podagra Macquart, 9 . 

 E. surinamensis Macquart, % . 



E. bifasciatus Macquart, % . 



Eighteen specimens from Rio de Janeiro and Chapada. The eyes 

 are pilose. Macquart describes them as bare in E. podagra and 

 surinamensis, but as that mistake was not an infrequent one with him 

 the discrepancy is of no importance. All three of these descriptions 

 apply well otherwise ; E. surinaviensis is, however, placed under the 

 group with the " cuisses posteriores greles," which may make the 

 synonymy somewhat doubtful. The femora in both sexes are dis- 

 tinctly, though not greatly, thickened. 



73. £ri!$talis taenia Wied. ? E. annuKpes Macq. 



Numerous specimens from Rio de Janeiro, Corumba and Uaricazal. 

 With Schiner's description of the thorax the determination seems 

 pretty certain, but there is a considerable variation in the color of 

 the legs, the four anterior ones often having considerable black. The 

 hind femora are only a little thickened. I believe Macquart's species 

 to be the same. 



74. Eristalis sp. 



,Four male specimens from Rio de Janeiro and Chapada resemble 

 tcenia closely, but seem distinct in the black pile of the frontal tri- 

 angle, and in the broadly interrupted presutural band. 



TKANS. AMER. ENT. SOC. XV. (36) NOVEMBER, 1888. 



