GERON.— USIA. 281 



proboscis black ; autennje black, relative length of joints as in 

 arf/entifrons, tips of first two joints narrowly pale, with greyish 

 hairs ; occiput black, with long yellow liairs above and greyish 

 ones below ; hind margin of eyes with small white scales. Thorax 

 velvet-black, dorsum covered with bright yellowish hairs, wliich 

 are greyish on the grey shouldei's ; underside ash-grey, with long- 

 grey hairs and some grey scales ; scutelluni black, yellow-haii'ed. 

 Abdomen black, with minute bright yellow fine scales and hairs ; 

 hind margins of segments with long defiexed grey hairs ; whole 

 dorsum with long thin greyish pubescence, which is denser at the 

 sides ; venter wholly covered with small silvery-white scales and 

 long grey hairs. Ler/s with coxse and fore femora black, former 

 with grey hairs ; posterior femora and all tibije pale tawny ; tarsi 

 black, middle metatai'si more or less pale at base ; legs almost 



Fig. 18. — Gcron albescens, Bnin., wing. 



bare except for a few short hairs below femora and the usual 

 minute tibial bristles. Wiii(js quite clear, Aeins pale yellowish on 

 basal half; halteres yellowish, knobs bright pale yellow. 



Leii(/th, 5-S nun. 



liedescribed from the original type from Balugaou, Puri Distr., 

 Orissa, 14. xii. 1908 {Caunter), and a second J fi'om Tambi, 

 Satara Distr., JBonibay, 2100 it., 22-2(J. \v. W12 {Gravehj), both 

 in the Indian Museum. 



^.i-vThe only definite character by which this species differs from 

 arffentlfrons seems to be the pale posterior femora in the 6 and 

 the larger size. 



Geuus USIA, Latr. 



Usia, Latreille, Hist. Nat. Crust. Ins. xiv, p. 300 (1804). 

 Volucella, Fabricius {nee Geoft'.), ]<>nt. Syst. iv, p. 412 (1794); id., 

 Syst. Antl. p. 114 (1805) ; Meigen, Kla.*s. i, p. 194 (1804). 



Genoxype, Volucella jlovea, Y. (Europe) ; by Eondani's desig- 

 nation. 



Rather small bare or nearly bare flies, sometimes of metallic 

 ground-colonr, sometimes with yellow and black markings. Head 

 hemisphei'ical, small, set rather low on the thorax ; epistome 

 short, proboscis prominent, at the base membranous, apical part 

 horny with extremely narrow labella ; palpi short, united to the 

 basal part of the membranous portion, which is entirely with- 

 drawable within the mouth-border. Antennae short, porrect, 

 hardly longer than head, approximate at base ; the first two joints 

 subequal ; 3rd elongate, spiudle-sha])ed above, blunt, witli spines 



