264 s. w. wiLi.isroN, m. d. 



narn>\voil basallv ; in tlic trin:\U' oiilv on tlir sih-oihI seti-mciit, which 

 is gently concave on its titles ; in the nude it does not attain its full 

 width till the tip of the third segment. 



IG. .^lelaiio<«(oiiiii Neitiiliini n. sp. 



% . — Leugth 7 mm. Allied to M. longicornis. Anteunfe less elongate, the three 

 joints of nearly equal lenjitli, the third not twice as long as wide. Face on the 

 sides with a slender stripe and spot of pollen, not punctulate. Abdomen narrow, 

 of nearly equal width throughout; fourth segment also with two yellow strigula>. 

 Four front tarsi wholly yellow. Wings hyaline, an elongate stiginatic spot and 

 narrow clouds on the cross-veins, brown. 



Two specimes, Chapaila. 



17. i»It*Inii«sf«iM« bncoplialiiN Wiedemann (Syrphns). 



Numerous specimens, C'ha}iada. AViedcniann's description applies 

 well to the males. The females are usually larger, reaching lo mm. 

 in length, and the niesonotum is not bronze colored, but deep shining 

 blue ; there is also a pair of yellow spots on the second segment. 

 The shape of the abdomen is more oval than usual among IMelano- 

 stomata. 



18. SyrpliiiN $;a<>iti*0!i<itaef UK Wied. 



A tlozen male spoeimens from Chapada may be this, but the wings 

 are only narrowly blackish in front, and only the hind tarsi may be 

 called white with their tip brown ; the other tarsi are more yellow or 

 brownish. The spots on the abdomen are small and oval. On each 

 outer end of the transverse suture, and on the post-alar callosities, 

 there is a small yellow spot. 



19. Syrpliiis erratic'iis n. sp. 



% 9- — Length 10 — 11 mm. Face, frontal triangle and cheeks, deep shining 

 blue ; on the sides of the face yellow, with whitish pollen ; frontal triangle with 

 black pile and a small opaque spot ; front narrowed above, across the middle with 

 a narrow poUinose baud, above which the color is more opaque, brown, or cop- 

 pery black. Antenna? brown; third joint pointed, more than twice as long as 

 wide. Eyes bare. Thorax bluish black, or blackish blue; niesonotum with three 

 opaciue black stripes, the median one linear, the outer ones acute behind. Scu- 

 tellum opalescent yellow; a slender crescentic brown band before the narrow 

 yellow base. Abdomen oval, black, moderately shining; second segment with 

 two yellow bands, not attaining the lateral margin; the first band is a little 

 broader exteriorly and interrupted in the middle; the second is crescentic. 

 emarginate in the middle behind, and acute on the outer ends. Halteres with a 

 yellow head. Wings hyaline, with the anterior part dark bi-owu ; the brown 

 tills out the first basal cell, and the submarginal, except an elongate space in the 

 middle behind. Legs pitchy brown ; the hind legs more black ; the middle 

 tibiie at the base yellow. 



Ten specimens, Chapada. 



