200 
60 One of the ungues longer than other in &. 
Plante hairy. 37. 
yy Ungues with some spines on the inner side, of 
equal length. 
6 Plantze hairy. 
38. Black, shiny. Anterior femora four spines, 
hind three. 
39. Black, shiny. Anterior femora many spines, 
hind three. 
40. Gray, blackish hairs. Anterior femora seven- 
teen spines, hind three. 
66 Plantze spinose. 
41. Black, shiny. Anterior femora ten spines, 
mid two, hind four. 
42. Blackish-gray. Anterior femora twenty-one 
to thirty spines, mid seven to twelve, hind 
eight to sixteen. 
886 Hind femora incrassatéd, spinose beneath. No 
spines on ungues. One claw longer than others. 
43. 
AA. Wings with one cubital areolet, produced 
from the prebrachial to the costa. 
Wings bare. Subcostal united to costal 
between middle of fore-border and tip 
of wing. 
a Femora simple. 44. 
aa Some or all the femora spinose on the under 
side. 
$B Ungues without spines. 
45. Palpi whitish. Halteres dark brown, white 
at base. 
46. Palpiyellowish-brown, Halteres white, knobs 
dark. 
BB Ungues of 2 with spine on inner side. 
47. Halteres pale-yellowish. Fore femora with 
two spines at the middle. Tarsi dusky. 
Hind tibize strongly ciliated. 
48. Halteres dusky, ferruginous. Fore femora 
with two spines between middle and end. 
Tarsi pale yellowish. Hind tibiz not 
strongly ciliated. 
aa Antenne with the last three joints elongated. 49. 
The following, described fully, are the most 
species : 
C. trichopterus, Hoffm. 
C. bipunctatus, L= C. geniculatus, Guér. 
C. hirtulus, Zett. 
Piceous. Head brown. 
AN ACCOUNT OF BRITISH FLIES. 
Antenne brown; plumes paler towards 
Fulvus, Macq. 
Serripes, Mg. 
Rufipectus, Wtz. 
Lineatus, Mg. 
Tibialis, Mg. 
Fasciatus, Mg. 
Femoratus, F. 
Venustus, Mg. 
Signatus, Mg. 
Ornatus, Mg. 
Teniatus, Wik. 
Calceatus, Hal. 
Pictus, Mg. 
abundant British 
the tips in the ¢. Thorax hairy ; hairs pale yellowish-white ; pectus 
pale in front, and with yellow streaks on each side, sometimes pass- 
ing into almost a reddish tinge. Abdomen covered with gray hairs, 
and having white sutures in the ¢; d¢ genitalia reddish - brown. 
