THE DIPTERA OF THE BRISTOL DISTRICT. 
59 
Asilid^; — The Hawk-flies : large flies that prey on other insects. 
Some of the larvae prey on other larvae. 
Leptogaster cylindricus (Deg.) Filton and Freshford. June. Some- 
times in numbers among" mowing grass. 
Dioctria reinhardi (W '.) Neighbourhood of Bristol (Verrall). 
atricapilla (Mg. ) Freshford, June, and V.R.P. 
,, celandica (L.) V.R.P. I have taken it in North Devon. 
rufipes (Deg.) Common throughout the district. 
flavipes (Mg.) Taunton in August. 
linearis (F.) Somersetshire (Verrall). 
Isopogon brevirostris (Mg - .) Withycombe (Slater), also C.J.W. 
Asilus crabroniformis (L.) Shirehampton in August, also V.R.P. 
The so called ' Hornet-fly,' a large, black and yellow and very 
shiny fly. 
Dysmachus trigonns (Mg.) Bitton in May. Rare. 
Machimus atricapillus (Fin.) S.M. , August, and C.J.W. 
Philonicns albiceps (Mg.) Leigh Woods and Henbury in September. 
Epitriptns cingnlatus (F.) Taunton in August. 
BoMBYLiDiE — Beautiful bee-like flies, with velvety bodies and long 
probosces. Seen in spring hovering over the flowers. 
Bombylius discolor (Mik.) S.M. and Keynsham in March and April. 
,, major (L.) S.M. from March to as late as June 18th, both 
these species are fairly common in spring - . 
,, canesce?is (Mik.) Very rare. Have seen it at Hanham 
and in North Devon in June. Brockley (C. Bartlett). 
,, minor (L.) Minehead (Blathwayt), and V.R.P., the latter 
record was possibly of B. canescens. 
Therevid^: — Black and grey flies that fly in hot sunshine, and 
often alight on a dusty path. Larvae occur in decayed tree trunks. 
Thereva nobilitata (F.) Freshford, May. 
plebia (L.) Freshford, May. 
,, marginata (Rossi) Freshford, June. 
,, fulva (Mg. ) Cranham, Gloucestershire. 
,, bipunctata (Mg.) V.R.P. 
Scenopinid^e — Small, flat-bodied black flies, with peculiar wing 
venation, often seen on windows ; they have been bred from larvae 
found in horsehair. 
Scenopinus fenestralis (L.) Bristol, S.M., &c. 
Cyrtid^e — Very curious flies of medium size, with small heads 
and globular bodies, and having no mouths, the buccal cavity being 
covered with a membrane. The wings are comparatively small. 
The larvae are parasitic on spiders ( Tegenaria), and the flies have 
a certain resemblance to the spiders. 
