THEItEVA. 297 



Table of Genera. 



First autennal joint nearly as long as head . . Phycus, Walk., p. 306. 

 First autennal joint much shorter than head. 

 Face and irons with long- dense pubes- 

 cence Thereva, Latr., p. 297. 



Face bare ; frons bare, or with com- [p. 302. 



paratively short pubescence in <$.... Psilocephala, Zett., 



Genus THEREVA, Latr. 



Thereva, Latreille, Precis Car. Gen. Ins. p. 167 (1796) ; id., Hist. 

 Nat. Crust. Ins. iii, p. 441 (1802). 



Genotype, Musca plebeja, L. (Europe). 



Head semicircular, placed closely on thorax ; frons slightly 

 produced towards antennae, densely pubescent in $ , shortly so 

 in $ , a transverse shining black callus present in £ ? f ace sloping, 

 covered thickly (as is all the lower part of the head) in cT with 

 dense pubescence, in 5 pubescence much shorter; three ocelli. 

 Proboscis of moderate length, rather upturned, labella large ; 

 palpi cylindrical, thin, pubescent. Eyes bare, contiguous in S 

 for some distance, wide apart in § . Antennas porrect, approxi- 

 mate at base, rather long; 1st two joints cylindrical, bristly and 

 pubescent ; the 2nd short ; 3rd narrowed at base, elongate- 

 conical, sometimes indistinctly annulated near base, bare, bearing 

 a short style ending in a minute filament. Thorax oval, densely 

 pubescent in c$ , less so in $ . Three to six presutural, two supra- 

 alar, one postalar. and one or two pairs of prescutellar bristles, 

 all strong and black, but the latter ones liable to variation. 

 Scutellum semicircular, with four marginal bristles; metanotum 

 small, bare. Abdomen conical, louger than thorax, with seven or 

 eight segments in 3 , the 8th always distinct in $ , forming basal 

 portion of ovipositor ; pubescence dense and furry in tf , shorter 

 in $ , and usually adpressed on basal segments. Genitalia not 

 prominent, but often visible ; ovipositor with a circlet of strong 

 black spines. Legs moderately long, slender; some black bristles 

 on coxae and anterior femora ; tibiae with rows of small bristles and 

 a circlet of spines at tip. Wings with normal Therevid venation ; 

 4th posterior cell generally closed or narrowly open. 



Range. World-wide, but apparently better represented in 

 Europe and North America. 



Life-history. Partly known ; larvae very active, occurring in 

 damp earth, under stones, and in similar places ; possibly they 

 feed, at least occasionally, on Lepidopterous larvae. 



Only four species are known for certain from India ; these may 

 be separated as follows : — 



Antenna? mainly bright brownish yellow. . kempt, sp. n., p. 298. 

 Antennae wholly black. 



Legs all blackish nujella, Wied., p. 299. 



