54 STKATIOJaTID^lC. 



upper facets much largei* tlian the small lower ones and generally 

 sharply delimiteel from them ; in 5 wide apart, with uniform 

 facets ; occiput with lower half considerably puffed out. Pro- 

 boscis retracted, « ith broad labella ; palpi rather inconspicuous. 

 Antennje elongate, first two joints subequal, 3rd spindle-shaped 

 or peg-shaped, with four annulations and a two-jointed apical or 

 subapical bristle. Thorax oblong, rather arched, moderately 

 pubescent ; humeri and posterior calli prominent ; scutellum with 

 two spines. Abdomen short and round, very arched, o-segmented. 

 Legs simple, short, weak. Wings with normal venation; 3rd 

 longitudinal vein forked or simple ; 4th vein with three endings,, 

 the 3rd often weak or absent ; posterior cross-vein absent, upper 

 branch of 5tli vein forming part of lovver side of discal cell, the 

 latter often indistinct : alulse well developed. 



Itange. Europe, Asia, North America, and one species from 

 Caft'raria. 



Life-Mstorg. The larva lives in moist mud among Cov.fei'vce. 

 The flies frequent leaves and flowers in the sunshine near streams- 

 and damp situations, \\ here they are very active ; on sunless daya 

 they settle on the underside of leaves near the ground. The 

 metamorphoses of several European species are well known. 



These insects are rather small, nearly bare, flies, generally of a 

 black colour with conspicuous yellow spots. 



0. signata is mainly a black species and 0. albomivans a yellow 

 one. 



27. Oxycera signata, sp. nov. 



(5 . -f/ead : eyes \vith dense brown pubescence, contiguous for 

 a considerable distance, leaving vertical and frontal triangles 

 about equal in size, black ; former wkh black hairs and three 

 brownish ocelli on an elevated prominence ; latter bare, shining ; 

 face black, witli a long oval patch of short snow-white pubescence 

 adjacent to the eye-margin on each side; no postocular orbit; 

 occiput black; proboscis orange-yellow; underside of liead with 

 short white hairs. Antennae black, first two joints subequal, 3rd 

 as long as first two together, with four annulations aiitl subapical 

 arista. Thorax shining black, with nioderately dense brownish- 

 grey piil)escence: a pair of widely separated, pale yellowish, 

 narrow, longitudinal dorsal stripes, not- quite reaching either 

 anterior or hind margin of dorsum ; an elongate briglit lemon- 

 yellow spot on each side of dorsum from prothoi*ax up to the 

 suture, and a large orange-yellow one on each posterior angle of 

 dorsum ; pleural black, with whitish pubescence and a callus-like 

 long yellow stripe from prothorax (where its end is contiguous to 

 the stripe on the side of the dorsum immediately above it) to root 

 of wing. Scutellum bright lemon-yellow, with brown pubescence, 

 hind margin black ; metanotum shining black, microsco]>ically 

 pubescent. Abdomen black, moderately shining, with micro- 

 scopic brown pubescence and a little white hair at sides of 1st 

 segment, which latter is narrowlv yellow at base ; a larce subtri- 



