DIPTERA. 141 
and second joints beset with long black bristles; second a little shorter 
than the first ; third long, spindle-shaped, rather slender, much longer than 
the second ; bristle rather stout, nearly as long as the third joint: chest 
and breast hoary ; chest beset with a few black hairs and bristles, its disk 
black, adorned with three hoary stripes: abdomen very slightly tapering 
from the base to the tip, nearly twice the length of the chest, clothed with 
black and white bristles and hairs, the latter most frequent on the under 
side, which is hoary, as are also the hind borders of the segments above ; tip 
shining, beset beneath with black bristles: legs black, thinly clothed with 
hoary hairs, armed with black spines ; hind-shanks and feet adorned be- 
neath with tawny down ; foot-cushions tawny: wings pale gray, dark gray 
towards the tips and thence along the greater part of the hind border ; wing- 
ribs and veins black; poisers yellow. Length of the body 6} lines ; of the 
wings 13 lines, A. Gamaxus, Fem. ? 
South America. 
Asitus Maricus,. Fem. 
Niger, antennis pedibusque nigris, tibiis fulvis apice nigris, alis cinereis. 
Body black: head mostly adorned with a dark tawny covering, 
clothed behind and beneath with tawny hairs; a few black hairs on the 
crown; face very convex towards the epistoma, beset with pale yellow 
bristles and nearer the feelers with black bristles; sides of the peristoma 
also beset with black bristles: eyes black; fore part nearly flat, its facets 
larger than those elsewhere: sucker clothed at the tip with short pale 
hairs : palpi clothed with pale yellow hairs: feelers black ; first and se- 
cond joints of nearly equal length, beset with black bristles ; third as long 
as the first and the second, yery slightly tapering from the base to the tip ; 
bristle much stouter than usual, tapering from the base to the tip, more 
than half the length of the third joint: chest thinly clothed with tawny 
hairs : abdomen slightly compressed, clothed with a few hoary hairs, nar- 
rower than the chest and much more than twice its length, very slightly 
tapering from the base to the tip which is shining and much compressed : 
legs black, clothed with short black hairs, beset with black bristles ; thighs 
with a tawny tinge; shanks tawny, black for one-third of the length from 
the tips ; claws at the base and foot-cushions tawny: wings gray ; wing- 
ribs and veins black ; foot-cushions tawny. Length of the body 9 lines; 
of the wings 14 lines. 
Port Philip. 
