52 
DIPTERA 
series in the first of which the tibial setse are short and slender, usually scarsely longer than the diameter 
of the tibia, and the larvae have no ambulacral setulae ; while in the second series the tibial setae are 
very strong and conspicous and the larvae as far as known have one or two transverse rows of ambulacral 
setulae on the ventral side of most of the body segments. 
TABLE OF GENERA 
a. An oval cell on.the media formed by the coalescence of the apical 
ends of the branches of this vein. 
b. Cubitus with a distinct petiole; recent form (PI. 4, Fig. I 4). 
bb. Cubitus apparently without petiole ; fossil (PI. 4, Fig. I 5). 
aa. No oval cell on the media. 
b. Proboscis elongated, beaklike. 
c. Media and cubitus unbroken. 
d. Media forks a very sJiort distance beyond the crossvein 
(PI. I, Fig. 8; proboscis, PI. 4, Fig. 16). . . 
dd. Media forks beyond the R-M crossvein at a greater distance 
than the length of its anterior branch; venation Sciara- 
like [compare PI. 6, Fig. 28, Sciara). Properly 
belongs with the Sciaridas 
CO. Bases of the branches of media and the cubitus defective. 
d. Palpi present; fossil (PI. 4, Fig. 17) 
dd. Palpi absent; recent forms. 
e. Ocelli wanting. West Indies 
ee. Three ocelli on the front. Australia (PI. 4, Fig. I 8). 
bb. Proboscis not elongated, or beaklike. 
c. Cubitus not forked; no free veins on the disk of the wing. 
d. Lateral ocelli widely remote from the eye margin; costa 
extends beyond the tip of the radial sector. 
e. The subcosta extends at least as far dlstad as the base of 
the radial sector ; media two branched (PI. 4, Fig. I 9). 
ee. Subcosta short; media simple (PI. 4, Fig. 20) . 
dd. Lateral ocelli nearly or quite contiguous to the eye margin; 
costa does not extend beyond the tip of the radial sector. 
e. Cell Rj very narrow, radial sector strongly arched (Pi. 6, 
Fig. 26) 
ee. Cell Rj not unusually narrow, radial sector nearly straight 
(PI. 6, Fig. 27) 
cc. Cubitus with tii'o branches. 
d. Basal portion of the anterior branches of both media and 
cubitus wanting, or media simple, or its petiole ivanting. 
e. Petiole of the media and the base of botli anterior and poste- 
rior branches of the cubitus wanting (PI. 4, Fig. 2 1 ). 
ee. Base of the posterior branch of the cubitus present. 
f. Subcostal vein rather long, extending at least one-fifth the 
length of the wing and ending in the costa. 
1. Genus Synapha, Meigen. 
2. Genus Pal^osynapha, Meunier. 
3. Genus Gnoriste, Meigen. 
Genus Eugnoriste, Coquillett. 
4. Genus Pal^ognoriste, Meunier. 
5. Genus Probol^eus, Williston. 
6. Genus Lygistorrhinus, Skuse. 
7. Genus Acnemia, Winnertz. 
8. Genus Azana, Walker. 
62. Genus Sceptonia, Winnertz. 
61. Genus Zygo.myia, Winnertz. 
1 ). 9. Genus Manota {==Cerato), Williston. 
