26 
DIPTERA 
metathorax arched. Abdomen slender, with seven segments in both sexes; in the male somewhat 
flattened, a httle thicker towards the middle, cylindrical at the base, in the female flattened claviform. 
Legs long and slender, the fore pair considerably shorter than the others; femora rather more slender 
than the coxae, shorter than the tibice; tibiae spurred; lateral spines extremel}- small; fore tibiie without 
lateral spines and the spurs small, intermediate tibiae with one lange oir the inner and one on the outer 
side, the spines on the latter widely separated, hind tibiae apparently with only one range of widely 
separated spines on the outer side. Wings moderately broad, rounded off at the base, longer than the 
abdomen, microscopically pubescent. Costal vein extending bej-ond the tip of terminating immedi- 
ately before apex of the wing ; subcostal vein joining the costa immediately before the base of the radial 
sector; Scj wanting; R2+0 rather long, arising considerably before the tip of Rj but ending in the costa; 
anterior branch of the media joining the margin immediately below the apex of the wing, consequently 
very close to the tip of the costal vein ; anal vein prolonged to the margin (PI. 3, Fig. I 8). 
Type species : P. dux, Skuse. 
Geographical distribution of species : 
I. P. dux, Skuse, Proc. Linn. Soc. N. S. Wales (2), Vol. 3, p. 1182 (i5i), Australia, 
pi. 3i, f. 7 (1S88). 
13. Genus NERVIJUNCTA, Marshall 
Nervijuncta. Marshall, Trans. New Zeal. Listit. Vol. 28, i8g5, p. 265 (1896). 
Characters. — Head nearly round, front not flattened. Eyes large, emarginato, almost meeting 
in front of the ocelli; ocelli three, large, situated almost in a line on the front. Palpi four jointed, short, 
first joint small; second lon;er and considerably swollen, the broadest part being in the middle; third 
joint rather shorter than the second, cylindrical, and rather narrow; fourth joint longest, very slender. 
Antennae shorter than the thorax; first joint of scapus short and broad, cupuliform ; second joint twice 
the length of the first, and not so broad, almost cylindrical, flagellum slender, cylindrical. 2 + i5 jointed, 
length of joints about three times their breadth, joints decreasing in diameter towards the apex of the 
antennae, pubescent, several stout setae, situated near the center ot each joint. Thorax highly arched, 
pubescent, with strong seta; on the lateral margin. Scutellum slim, circular, bordered with setae on the- 
posterior margin. Metathorax acclivous. Abdomen racher flattened, seven jointed, slender in front but 
becoming broad posteriorly. Forceps of male two jointed, first joint almost spherical, crateriform at the 
apex, densely hair}'; second joint double the length of the first, cylindrical, hairy. Legs slender, coxas 
much stouter than the femora, almost naked; femora about twice the length of the coxae, pubescent, 
tibiae slender, in the fore leg rather more than one-half the length of the larsus, in the intermediate legs 
very slightl}' longer than the tarsus, in posterior legs rather longer than the tarsus, and with two lows of 
few, but rather long and slender spines; spines very distinct; metatarsus long, that of intermediate and 
posterior legs with a few minute prickles. Wings larger than the abdomen, rounded at the apex, and 
cuneiformly narrowed at the base, pubescent on the surface. Subcostal vein a shoit tooth not joining 
the costa nor the vein Rj ; Rj joining the margin at about two-thirds the length of the wing; radial 
sector arising from Rj at about one-third the length of the wing, its anterior branch slightly arcuated; its 
posterior branch joining the tip of the costa almost at the apex of the wing; fork of the media situated 
just beyond the fork of the radial sector, branches not divergent; the anterior branch of the cubitus 
almost straight, its posterior branch arcuate; anal vein incomplete not reaching the maigin of the wing; 
the R-M crossvein obliterated by the coalescence of a small section of radius and media (PL 3, Fig. 2 I ). 
