COLE OP TER A . 
s« 
Q. Elytra covering the abdomen. 
p. 531.SCYDM/ENIDJE. 
QQ. Elytra not covering the entire 
abdomen, p. 533. 
SCAPHIDIIDjE. 
OO. Posterior coxae approximate. 
P. Antennae gradually thickened, or 
clavate; posterior tarsi not wid¬ 
ened. p. 529.SlLPHIDiE, 
PP. Antennae setaceous, filiform, 
serrate, pectinate, or flabellate, 
rarely with three somewhat larger 
terminal segments, in which case 
the tarsi are widened. 
Q. Anterior coxae long, with dis¬ 
tinct trochantins. 
R. Abdomen with seven or eight 
ventral segments, p. 550. 
LAMPYRIDiE. 
RR. Abdomen with only six 
ventral segments, p. 552. 
MALACHIIDiE. 
QQ. Anterior coxae without tro¬ 
chantins. p. 553 ..Lymexylid,e. 
GG. Hind tarsi either only three-jointed or four-jointed, 
but apparently three-jointed, the third segment being 
small and concealed in a notch at the end of the sec¬ 
ond segment. (See also GGG.) 
H. Wings fringed with long hairs. 
I. Abdomen with six or seven ventral segments. 
\ Tarsi four-jointed, the third segment small and 
concealed in a notch at the end of the second 
segment, p. 534. Corylophid^e. 
JJ. Tarsi three jointed. 
K. Antennae slender, verticillate, with long hair, 
abdomen not prolonged, p. 533. 
TRICHOPTERYGIDiE. 
KK. Antennae short, not verticillate, abdomen 
prolonged, p. 533. Hydroscaphid;E. 
II. Abdomen with only three ventral segments, 
p. 533 ...SPJEERIIDiE. 
HH. Wings not fringed with hairs. 
