SOUTH AMERICAN DIPTERA. 273 



tennal joint, and there are bristles on the lateral margin of the 

 mesonotuni, on the border of the scutellum, and an even row of 

 about ten in front of the scutellum. The veins of the wings in two 

 are distinctly clouded, in the other two scarcely at all. The front 

 of the female is narrow and red. The middle legs have bristles and 

 spurs as in V. prescutellaris. 



49. Voliicella preseiitellari^i n. sp. 



% . — Length 11 — 12 mm. Frontal triangle black, but largely obscured by tbe 

 reddish yellowish pollen ; in the middle with an acute tubercle, the profile show- 

 ing two straight lines meeting at an angle of about one hundred degrees. An- 

 tennae reddish yellow, the distal part of the third joint narrowed, though but 

 little excised ; arista long and thickly plumose. Face translucent yellow, only 

 shallowly concave below the antennte, the tubercle large and obtuse ; lower mar- 

 gin of the cheeks nearly straight, meeting the plane of the occiput at an angle 

 of about one hundred and ten degrees. Mesonotnm blue, with strong violet re- 

 flections ; pile moderately abundant, golden yellow. Scutellum translucent yel- 

 low, with black pile on the disk. Pleurai blackish brown, somewhat dusted 

 above; pile yellow. The sides of the mesonotum, mesopleurse, post alar callosi- 

 ties, a transverse row in front of the scutellum, and the margin of the scutellum 

 with strong black bristles. Abdomen Musca-Uke in shape, with erect black and 

 yellow pile : first segment black, except the lateral angles; second segment yel- 

 low, with a median stripe extending along the anterior suture outward, black or 

 brownish black; third segment yellow, with a posterior band, dilated in the 

 middle into a stripe that reaches the front margin, black ; fourth segment black 

 with blue reflections, and with the anterior angles reddish or yellowish. Legs 

 black, with black pile; tibise and metatarsi more or less reddish ; middle femora 

 on the posterior side near the tip with two or three bristles, and the middle tibiae 

 with three or four well-defined spurs at the tip. Wings nearly hyaline, the outer 

 part brown or brownish, behind tinged with blackish ; marginal cell closed some 

 little distance before the costa. 



9-— Front shining black, with black pile; the narrow orbit below the ocelli, 

 and the sides below, thickly grayish yellowish poUinose; corresponding to the 

 tubercle in the male, there is an obtuse convexity. Third antenual joint broader. 



Eleven specimens, Chapada. The color of the abdomen varies 

 posteriorly, so that it sometimes appears black, with the sides of the 

 third segment in front reddish or yellowish. 



50. Volucella persimilis n. sp. 



Remarkably like the preceding, though certainly distinct. The 

 frontal triangle of the male is yellow, not black, and is only gently 

 convex, not angular in profile ; the third joint of the antennae is less 

 narrowed distally, and the cheeks have a black or brown stripe. In 

 the female, the front is translucent reddish yellow, without the con- 

 vexity and depression of V. prescutellaris. In both sexes the lateral 



TRANS. AMEE. KNT. SOC. XV. (35) NOVEMBEK, 1888. 



