DIP TER A. 427 
extent as to cause the free part to appear like a 
cross-vein. 
I. Antenna with a terminal style or bristle. 
J. Antenna with a terminal bristle, p. 474. 
PLATYPEZIDiE. 
JJ. Antenna with a terminal style. 
K. Front with grooves or a depression beneath 
the antennae, p.476. Conopide. 
KK. Front convex beneath the antennae, 
p. 470. Syrphide. 
II. Antenna with dorsal bristle. 
J. Head extremely large, and with nearly the en¬ 
tire surface occupied by the eyes (Fig. 577). 
p. 473. Pipunculide. 
JJ. Head not of the type represented by Figure 
577 . 
K. Wings with a vein-like thickening, the spu¬ 
rious vein, between veins III and V (Fig. 574). 
p. 470.SYRPHIDE. 
KK. Wings without a spurious vein. 
L. Front with grooves or a depression beneath 
the antennae, p 476. Conopide. 
LL. Front convex beneath the antennae. 
p. 470. Syrphid^e. 
AA. Flies in which the abdomen is indistinctly segmented, and the 
two legs of each segment are widely separated by the broad ster¬ 
num. The adults live parasitically upon birds, mammals, or the 
Honey-bee. 
B. Compound eyes present; wings present or absent, p. 487. 
HlPPOBOSCIDE. 
BB. Both compound eyes and wings absent. 
C. Halteres present; tarsal claws of ordinary form. Adults 
parasite upon bats. p. 489. Nycteribiide. 
CC. Halteres absent; last segment of tarsus with a pair of comb¬ 
like appendages. p.489. BrAULIDE. 
Suborder ORTHORRHAPHA (Or-thor'rha-pha). 
The Straight-seamed Flies . 
To this suborder belong those families of flies in which 
the pupa escapes from the larval skin through a T-shaped 
