SCEXOPINUS. 311 



Life-history. The metamorphoses have been well described by 

 Bouche, Dufour, aud others. The larva is amphipneustic, hard, 

 cylindrical, very elongate, apparently of twenty segments, with 

 small head and two small styles at tip of body, moving in a 

 serpentine manner; abdominal segments with transverse rows of 

 bristles. Pupa resembling that of Thereva. The larva was at 

 first thought to live on carpets, rugs, and similar articles, but it 

 is now believed that they live ou the other larvae (of TrxEtDiE and 

 Pulicidje, for instance) that occur in these habitats. They are 

 certainly carnivorous, and probably feed on the larvae of many 

 different groups of insects, judging from the various situations in 

 which Scenopinus fenestralis has been found. 



The ScENOPiNiDiE are a very limited but distinct family, con- 

 spicuous by the absolutely bare body and characteristic venation, 

 coupled with the two pulvilli and bristle-like empodium. Their 

 actual relationships have given rise to various opinions, their 

 characters indicating diverse affinities, such as to Xylomyia, the 

 Thereytd^;, and Mydaidje. Verrall places them with the latter 

 in a super-family, Dermatina, between the AsilidjE and the 

 Tieereyid.E: Lundbeck and Kertesz put them between the 

 Therevidje and the E.upid./e ; Schiner with Mydaidjg between 

 Asilid^; and Thekevidje; Aldrich between Therevim: and 



BOMBYLIID^E. 



Most of the known species belong to the genus Scenopinus. 



Genus SCENOPINUS, Latr. 



Scenopinus, Latreille, Hist. Nat. Ins. Crust, iii, p. 463 (1802), xiv, 



p. 392 (1804). 

 Atrichia, Schrank, Fauna Boica, iii, p. 54 (1803). 

 Cona, Schellenberg, Gattung. d. Fliegen, p. 66 (1803). 

 Hypselura, Meigen, Illig. Mag. ii, p. 273 (1803). 

 Astomn, Lioy {nee Oken, 1815), Atti Istit. Yeneto, (3) ix, p. 762 



(1864). 



Genotype, Mascafe lestralis, L. ; b} r Latreille's designation. 



Head transverse, short, semicircular, flattened behind ; not 

 closely applied to thorax, but no obvious neck ; frons generally 

 flush with eyes ; three ocelli ; proboscis withdrawn ; palpi incon- 

 spicuous, cylindrical, tip bristly. Eyes bare, generally contiguous 

 in c? , in such cases upper facets larger than lower ones; in $ 

 wide apart. Antennae sub-contiguous at base; 1st and 2nd joints 

 short ; 3rd elongate, drooping, strap-shaped, normally without 

 style or arista, hut if present, it is concealed in a depressed pit. 

 Thorax longer than broad ; dorsum rather flattened, with a little 

 scaly pubescence; pleurae minutely pubescent, mesopleura with 

 an obvious depression on front part for reception of the short 

 thick front femora ; scutellum short, broad, flat. Abdomen rather 

 flat, oblong, tip flattened cone-shaped, 7- or 8-segmented ; middle 

 segments bearing a transverse impressed line across the centre ; 



