DIP TER A. 
425 
third segment either with or without a style or bristle, but not 
divided into subsegments. 
C. Antennae consisting apparently of a single globular segment 
bearing a long bristle; wings with some stout veins near the 
costal margin and other weaker ones extending across the 
wing unconnected by cross-veins (Fig. 581). p. 475 .Phorid^e. 
CC. Flies that do not present the type of venation represented 
by Figure 581. 
D. Cells V and first V 2 not separated (see Fig. 571 for an ex¬ 
ample of this type). 
£. Vein III with a knot-shaped swelling at the point of 
separation of veins Ilia-P3 and III4 + B; the cross-vein 
1 II-V at or near this swelling; no suture immediately 
above the antennae, p.467. Dolichopodid^e. 
EE. Vein III with or without a swelling at the point of 
separation of veins Ilia-4-3 and Ilh-K; the cross-vein 
III-V more remote from base of wing; a suture immedi¬ 
ately above the antennae, p .479 . Muscidte. 
DD. Cells V and V 2 separate. 
E. Vein III four-branched. 
F. Venation intricate, due to an unusual anastomosing of 
the veins (Fig. 555). p. 459 .Nemistrinidje. 
FF. Venation not of the type represented by Figure 555. 
G. Vertex of head distinctly hollowed out between the 
eyes (Fig. 557); eyes never contiguous, p. 460. 
ASILIDiE. 
GG. Vertex of head not hollowed out between the eyes; 
eyes often contiguous in males. 
H. Alulets very large, p. 458. Acroceridje. 
HH. Alulets small or rudimentary. 
I. Cell V 8 present. 
J. Vein Ills ending before the apex of the wing 
(Fig. 562). p.462. Apiocerid^e. 
JJ. Vein Ills not ending before the apex of the 
wing. 
K. Empodia pulvilliform, />., with three mem¬ 
branous lobes beneath the tarsal claws (Fig. 
495). p. 456. Leptid^e. 
KK. With only two membranous lobes beneath 
the tarsal claws, p. 464. Therevid^e. 
II. Cell V 3 obliterated by the coalescence of veins 
Vs and VIIi. 
