1. THEREVA 549 



the male, besides the black chsetotactic bristles. Abdomen of the female 

 with the seventh abdominal segment and the ovipositor shining black. 

 Prsescutellar bristles two pairs. 



An extremely beautiful bright tawny fly. 



S. Face and frons entirely covered with dull golden dust; frons bearing con- 

 spicuous long black pubescence which extends (though gradually contracting) 

 down the sides of the face almost to the bottom of the eyes but becomes almost 

 restricted to a single row of hairs on- the lower part ; all the rest of the face 

 with long dull yellow drooping pubescence which becomes paler on the lower 

 part and which is divided by the long niouth-oi^ening ; lower part of the face, 

 jowls, and loAver part of the back of the head covered with more whitish 

 dust, while the pubescence on the rather wide jowls is long and dull yellow 

 with (almost always) a few black hairs intermixed though not enough to call a 

 clump ; lower part of the back of the head with long shaggy pale yellow 

 pubescence, but the upper part covered with tawny dust and with denser 

 shorter and tawny pubescence, while out on the middle part of the back of 

 the head are about six (or fewer) irregular black bristles, and there is a single 

 postocular row of about twenty long black bristly hairs on the upper half of 

 the head which curve over at their tips and which are connected with the 

 black pubescence on the dull yellow vertex ; the conspicuous tuft of long 

 black hairs on the frons leaves the hairs quite close to the base of the antennae 

 dull yellow. Eyes touching for almost one-third of the distance' between the 

 occiput and the antennae, and with the facets almost imperceptibly diminish- 

 ing in size from the upper part downwards. Antennse entirely obscured by 

 dull yellow dust on the two basal joints and the base of the third joint, but 

 the third joint is dull dark brown with its basal annulation rather orange; 

 the stout black bristles on the apical half of the basal joint and on the second 

 joint conspicuous, but the finer pubescence on the basal half of the first joint 

 dull yellow. 



Thorax and scutellum with the ground colour apparently dull brownish 

 orange, but entirely covered with almost erect dense tawny, dark tawny, and 

 yellow pubescence besides the strong black chastotactic bristles, but a close 

 examination shows that (almost always) numerous thin black hairs are 

 scattered all over the disc, and these black hairs (except when very few) 

 cause a darker tawny appearance on that part ; the chastotactic bristles 

 placed as usual (fig. 311) but the prsesutural bristles often irregular (some- 

 times four on one side and two on the other), and the prjiescutellar bristles 

 always present in two pairs ; pleura with rather long dense pubescence 

 which is tawny on the upper part but paler below, and the tuft on the meta- 

 pleurse lai-ge, long, dense, and tawny. Scutellum with rather longer tawny 

 pubescence, and with fewer or none of the longer thin black hairs ; metanotum 

 bare of pubescence but covered with greyish yellow dust. 



Abdomen entirely dull brownish orange but covered with dense tawny 

 pubescence, and in some lights the second to fifth segments with sharjDly 

 defined perfectly equal bare orange hindmarginal hems, of which a trace 

 exists on the sixth segment ; pubescence apparently all tawny but a few black 

 hairs can be traced on a middle dorsal stripe, though not on the hindmargins, 

 and occasionally these black hairs are numerous enough to form a fairly con- 

 spicuous black dorsal stripe on the six basal segments, and may even 

 extend across the hindmargins of the sixth and seventh segments and even on 

 to the disc of the seventh and genital segments. Belly with a dull blackish 

 ground colour obscured by yellowish grey dust, and with conspicuous yellow 

 hindmargins to the second to sixth segments and a tawny hindmargin 

 to the seventh segment ; pubescence long but not conspicuous, as it is thin 

 erect and pale when compared with that on the dorsal side. Genitalia with 

 two large broad tawny side-plates which end in narrow tawny claspers, 

 between which on the upper part at the base is a jiair of lamelliB which are 

 shorter and darker than in T. nohilitata, while the genitalia are conspicuously 

 bright tawny when seen from beneath and bear long rather bristly tawny hairs. 



