1893.] MR. E, E. .VrSTEN 057 ^fEW DIPTEEOFS IlfSECTS. 155 



metallic yellow on the sides of the dorsum and on the pleurae, 

 metauotum and a faint patch on each side above the middle coxte 

 brown. ScKtellum dull yello^v. Ahdomen : second segment with a 

 narrow, posteriorly conca^■e, pale bro^n transverse band near the 

 hind margin ; third segment \\itli a brown transverse band ^\ hich 

 is very narrow and close to the hind margin in the middle, but at 

 the sides is broader, reaches to the hind margin, and has a ragged 

 antei'ior edge ; fourth segment with tlie extreme hind margin, a 

 small median posterior triangle prolonged into a faint median line 

 which almost reaches to the anterior margin of tlie segment, and a 

 quatlrate area in each posterior angle, occupying about one-third of 

 the length of the segment, brown ; the inner anterior angles of the 

 quadrate areas are considerably prolonged, so that they run like a 

 sharp thorn into the yellow portion of the segment on each side ; 

 fifth segment nearly wholly yellow, a narrow median stripe starting 

 from the anterior margin of the segment, but becoming obsolete 

 about halfway, and an ill-defined patch in each posterior angle, 

 from which a faint and almost obsolete streak ru]is forwards and 

 slightly inwards, faintly brown ; genitalia brown at the tip : the 

 abdomen is clothed with very short and sparse appressed black 

 pile ; the thorax and scutellum almost bare. Legs uniformly pale 

 yellow ; first joint of posterior tarsi slightly swollen. Winr/s 

 rather narrow ; third longitudinal vein concave posteriorly; sub- 

 costal cell orange. 



Brazil, region of the Amazons (Bates) : one specimen. 



Bacciia crocata, sp. n. (Plate \. ng. 5, $ .) 



2 . Length 7. 4 to 9| mm. 



Saffron-i/flJov: ; ahdoiaen xvith hroivii bauds and indentations, 

 centre of dorsum of thorax shinin;/ brown, with yelloivish cinereous 

 ■pollinose stripes : winr/s suffused with saffron-yellow, somewhat 

 darlcer on the basal half along the costal side ; alulce rudimentary : 

 legs u'holly yellow; the posterior femora of the smallest specimen have 

 a narrow incomplete faint brownish band towards the tip. 



Face and cheel-s pale opalescent yellow, clothed with sliort pale 

 pile ; face tuberculate, receding. Front satfron-yellow, pollinose, 

 rather more than the posterior third ciuei'eous-bronze polhnose, 

 from winch a sharply defined brown median stripe ruiis to the 

 base of the antenniferous projection ; in a smaller specimen (T^ mm. 

 in length) this stripe is bi'oador and runs right o\'er the anten- 

 niferous projection to the base of the antennae ; immediately 

 above the antennas is a round black dot. Antenna' orange, short, 

 third joint rounded, arista brown, yellow at the base ; ocelli i*emote 

 from the vertex. Occiput fringed w ith golden-yt-llow hairs. The 

 pollinose stripes of the dorsum of the thorax consist of a very fine 

 median one, and a much broader stripe on either side of this ; 

 all three ai-e abbreviated lji;fore reacliing the scutellum, but the 

 median one is somewhat the; longer ; the brown stripe outside each 

 lateral pollinose one is the broadest and darkest of all, and is 

 divided bv the transverse suture; the sides of the dorsum aiid 



