[February 1885. BULLETIN. BROOKLYN ENTOM. SOC. VOL. VII. 131 
H.—Abdomen with only four visible segments..... .......... Pipizinae. 
- HE.— Abdomen with five or six visible segments. 
F,—Face rounded, receding, not tuberculate, pilose............ Pipizinae. 
FF.—Face tuberculate, or at least the oral margin in front is not receding 
but more or less produced. 
G.—Front long, much narrowed above in the female, cheeks narrow, 
face considerably narrowed below, abdomen frequently contracted 
beyond the base, more or less slender................. Bacchinae. 
GG.—Face widest below, or at least but slightly narrowed. 
H.—Abdomen in outline linear or oval, never narrowed beyond the 
base, that is in outline not club-shaped. 
JI.—Color chiefly reddish or lutescent.............. Brachyopinae. 
IT.—Color not chiefly reddish or lutescent. 
J.—Metallic green, metallic green and black, or black species, 
rarely with luteous markings at base of abdomen, humeri 
and face; abdomen never with entire shining cross-bands.... 
Chilosinae. 
JJ.—Black or greenish black species with yellow or yellowish 
stripes or bands, or at least with entire shining cross-bands 
on abdomen. 
K.--Face black; abdomen usually slender, with yellow or 
greenish yellow interrupted cross-band....Melanostominae. 
KK.-—Face partly or wholly yellow; abdominal markings 
yellow. 
L.—Dorsum of thorax with yellow ‘lateral stripes....... 
Xanthogramminae. 
IL.—Dorsum of thorax without yellow lateral stripes.... 
Syrphinae. 
HH. —Abdomen contracted beyond the base, in outline more or less 
club Sshaped(sismialll speciegeam smaaecretlee sess lea Ascinae. 
CC. —Marginal cell of the wing closed and petiolate....... ........ Volucellinae. 
AA.—Anterior cross-vein near or beyond the middle of the discal cell, usually oblique, 
the hind femora frequently thickened. 
M.—Antennz with a dorsal bristle. 
N.—Third longitudinal vein bent deeply into the first 
posterior cell. 
0.—Marginal cell closed and petiolate.....Bristalinae, 
00.—Marginalyeell open......... ..-.-- Maliotinae. 
NN.—Third longitudinal vein, only gently curved. 
P.—Arista plumose, 
Q. —Marginal cell closed.......... Volucellinae. 
Q@.—Marginal cell open.......... Sericomyinae. 
PP.—Arista bare or pubescent. 
f.—Thorax with distinct yellow markings....., 
Milesinae, 
RR.—Thorax without yellow markings...... 
Xylotinae. 
MM.—Antenne with a terminal style...... a fees he Cerinae. 
