302 Mr. F.Walker's Characters of undescribed Diptera 



slightly obtuse and somewhat rounded angle at its flexure, much 

 curved inward from thence to its tip, which is at some distance in 

 front of the tip of the wing ; discal transverse vein straight, parted 

 by somewhat less than its length from the border and from the 

 flexure of the praebrachial ; alulae dingy whitish. 



Length of the body 3 lines; of the wings 6 lines. 



Mexico. 



Genus Masicera, Macq. 



Masicera disputans. 



Mas. — Nigra, gracilis, setosa, capite albo, frontalibus peran- 

 gustis, palpis ferrugineis, antennarum articulo 3° longo 

 gracili, arista tenui, thorace cinereo vittis duabus angustis 

 nigris, pectore albido, abdomine tenuissimo, segmentis albido- 

 fasciatis, lateribus basi sub-rufescentibus, pedibus longius- 

 culis, alis obscure cinereis apud costam nigricantibus, vena 

 praebrachiali angulum perobtusum fingente, vend discali 

 transversa sub-undulata. 



Male. — Black, slender, bristly: head white; vertex black; 

 front prominent ; frontalia very narrow, widening in front ; 

 facialia without bristles; epistoma not prominent; palpi ierru- 

 ginous ; antennae almost reaching the epistoma ; third joint slender, 

 linear, rounded at the tip, about four times the length of the 

 second ; arista very slender, except near the base, nearly twice 

 the length of the third joint ; thorax cinereous, with two slender 

 black stripes ; pectus whitish ; abdomen very slender, with a 

 whitish baud on the fore border of each segment ; slightly reddish 

 on each side towards the base ; legs rather long and slender ; 

 wings dark grey, blackish along the costa ; veins black; prae- 

 brachial vein forming a very obtuse angle at its flexure, straight 

 from thence to its tip, which is at a little in front of the tip of the 

 'wing; discal transverse vein slightly undulating, parted by much 

 less than its length from the border and by a little less than its 

 length from the flexure of the praebrachial ; alulae cinereous. 



Length of the body 3^ lines ; of the wings 6 lines. 



Mexico. 



Masicera gentica. 

 Alas. — Nigra, gracilis, capite albido, frontalibus atris, anten- 

 narum articulo 3" longo apice obtuso, arista gracili, thorace 

 cinereo vittis quatuor nigris, abdominis segmentis cinereo- 

 fasciatis, pedibus longiusculis, alis cinereis, vena praebrachiali 



