MK. WALKER ON DIPTERA COLLECTED IN AMBOTNA. 157 



whole length from the epistoma, which is slightly prominent. Eyes 

 pubescent. Antennae reaching the epistoma ; 3rd joint linear, some- 

 what obtuse at the tip, about six times the length of the 2nd ; ai-ista 

 long, stout for about one-third of its length. Thorax with whitish 

 bloom, and with two very slender black stripes. Abdomen oval, not 

 longer than the thorax, somewhat tessellated on account of its whitish 

 glancing bands being interrupted on each side. Legs stout. Wings 

 grey, blackish at the base and along part of the costa ; praebrachial 

 vein forming a rounded and slightly obtuse angle at its flexure, beyond 

 which it is slightly curved inward ; discal transverse vein nearly 

 straight, parted by much less than its length from the border, and by 

 less than its length from the flexure of the prsebrachial ; alulaj white. 

 Length of the body 4 lines ; of the wings 8 lines. 



Gen. Teichopeosopa ? Macq. 



45. Trichoprosopa? marginalis, n. s. Nigra, elongata, capite an- 

 tico albo, antennarum articulo 3° fusiformi, thorace cinereo vittis dua- 

 bus nigris humeris albidis, pedibus robustis, alis nigricantibus elongatis 

 margine postico strigisque cinereis, alulis cinereis nigro marginatis. 



Black, elongate, bristly. Head white in front ; two long stout bristles 

 on the vertex, and one on each side of the epistoma, which is promi- 

 nent ; frontalia with bristles ; facialia without bristles. Antennae 

 almost reaching the epistoma ; 3rd joint fusiform, rather obtuse at the 

 tip, about four times the length of the 2nd ; arista long, stout for 

 about one-third of its length. Thorax shghtly cinereous; humeri 

 whitish ; two dorsal black stripes. Legs stout. Wings blackish, 

 elongate, cinereous along the hind border, and with cinereous streaks 

 in some of the areolets ; praebrachial vein emitting a stump and form- 

 ing an obtuse angle at its flexure, beyond which it is undulating and 

 joins the cubital vein at some distance from its tip ; discal transverse 

 vein undulating, parted by about half its length from the border, and 

 from the flexure of the prffibrachial ; alulae cinereous, black bordered ; 

 halteres black. Length of the body 6| lines; of the wings 12 lines. 



Subfam. Dexides, Walk. 



Gen. Dexia, Meigen. 



46. Dexia V alulifera, n. s. Mas. Nigra, angusta, capite albo, 

 frontalibus piceis perangustis, oculis nudis, palpis fulvis, antennis 

 piccis basi fulvis, thorace subcinereo fascia media vittisque tribus an- 

 ticis albis, abdoniine cylindrico fasciis duabus latis apiceque chalybstis, 

 pedibus longis, alis angustis fuscescentibus, alulis pallida flavis,halteri- 

 bus albis. 



Male. Black, narrow, with a few slender bristles. Head white, shining ; 

 frontalia piceous, veiy narrow ; facialia without bristles, except by 

 the eiMstoma, which is not prominent, and has a black point on each 



