TWO NEAV AND UEMAIíKABLE SYKPHIDAE 575 



sba|)e of tbe scutellum and coloour of legs, it agTeeswitli Lepidostola 

 Jenníngsi Shannon, 1925 (Panamá), but this species lias an auterior 

 and au interrupted ínedian cross band of yellow scales on tlie meso- 

 notuiu as well as tbe posterior one. Tbe nietasteniuní in ortalina is 

 membranous bebiud as in Jenningsi. 



Localities: La Rioja (Collection Museo Historia Xatural Buenos 

 Aires); Alta Gracia, Córdoba (2ü, 1. 27, R. C. Sbanuon) ; Vipos, Tu- 

 cuman (4 Marcb, 27, E. del Ponte). 



Genus VOLUCELLA Geotfroy 

 Subgeims Volosyrpha, uew subgeuns 



Tbe subgenus is based upon a species possessing severa! reinar- 

 kable cbaracters. Difters from otber subgenera of tbe genus by tbe 

 presence of a frontal tubercle, a long arista witli sbort dense plumo- 

 sity above and below and scattered long bairs above, tbe apex bare ; 

 tbe usual dorsal and ventral surfaces developed iuto tbree planes and 

 in baving tbe bind tibiae greatly enlarged and arcuated. 



Phalacromyia is tbe nearest related subgenus. 



Type species : V. ( V.) tibiaUs, new species. 



Volucella (Volosyrpha) tibialis, uew species 



Description of species. — Female : Front sbining black, ratber nar- 

 row, diverging downward, ocelli raised on a large tnbercle, evidently 

 a dense tuftof black bair norrually present between tbe ocelli as a 

 distinct granulóse área is present ; a second and very distinct tu- 

 bercle present a little above middle of front ; pile on front scattered 

 and palé in colour ; antennae yellowisb brown, first and second joints 

 sbort; lengtb of tbird joint about two and one-balf times its widtb 

 at base, progressively but little narrowing apically; arista longer 

 tban lengtb of antenna, tbe apical sixtb bare but remainder witb 

 dense, black and sbort plumosity above and below and scattered long- 

 bair above ; face dark, región of tubercle brownisb, a yellow stripe 

 extending from lower oral margin to eye ; face fíat below antennae, 

 raised to a tubercle aiul below tubercle to oral margin straigbt. Tito- 

 rax: Bhick witb black bristles and pile, tbe pile ligbter along sides 

 of mesonotum, also a pair of submedian stripes of liglit pile on ante- 

 rior balf of mesonotum. Scutellum of very curious sbape, tbe normal 

 dorsal and ventral surfaces developed into tbree planes, an antero- 



