26 DIPTERA. 
straw-yellow, a little transparent, with insignificant black pile; first segment with a black spot under 
the scutellum ; fourth segment shining black ; the hind margin of the first segment with some strong 
bristles, and the hind margin of the second segment with some spines, the middle ones of which stand 
irregularly forward, and the sides with some long macrochwte ; third segment with spines along the 
whole hind margin, the middle ones stouter and accompanied by 5 or 6 macrochete; fourth segment 
densely beset with spines, as is also the middle portion of the venter ; anus reddish. Legs black ; under- 
side of the femora with long black hairs and bristles ; tibie outwardly beset with bristles, those of the 
front pair short, and those of the middle pair the longest; foot-claws and pulvilli yellow, in the male 
longer and surrounded by black hairs, the claws with black tips; front tarsi of the female a little dilated. 
Tegula and wings brownish-grey ; small cross-vein placed on the middle of the discal cell; apical and 
posterior cross-veins oblique and curved. 
Hab. Mexico, Ciudad in Durango 8100 feet (Forrer). 
Three male and three female specimens. A fourth male specimen from Cache, 
Costa Rica (Rogers), differs from the others in the more rufous coloration of the 
abdomen. 
S. bicolor, Will. (Trans. Am. Ent. Soc. xiii. p. 304), from New Mexico, Arizona, &c., 
seems to be a closely allied species, but it has yellow side-borders to the thorax and 
reddish tibiee. 
12. Saundersia truncaticornis, sp.n., ¢. (Tab. II. fig. 4.) 
Thorax and scutellum blackish; head and abdomen yellow, the latter with the fourth segment black; cheeks 
with a bristle; antennez black, with the basal joints dark rufous ; legs fulvous; wings brown. 
Length 10 millim. 
Head ochraceous; face perpendicular, prominent at the oral margin; cheeks with weak hairs and a black 
bristle ; vibrissce above as well as beneath accompanied by several other bristles; beard pale yellow; 
front blackish-grey, scarcely narrowed behind, the median band piceous, almost black; frontal bristles 
strong, two or three of them descending beneath the base of the antenna. Antenne black, the two 
basal joints somewhat reddish ; third joint a little longer and notably broader than the second, truncated 
at the end; arista at the base rather distinctly jointed, gradually tapering towards the end, microscopically 
pubescent. Proboscis black, projecting beyond the head. Thorax black, with a dark cinereous 
tomentum, the tomentum on the front part more clear and showing the beginning of four longitudinal 
black stripes; the surface bearing a rather dense black pile and long macrochete; pleure grey ; 
scutellum black, without spines but with macrochete, those at the hind margin longer and more 
backwardly directed. Abdomen very convex, transparent straw-yellow ; a spot under the scutellum 
and the whole fourth segment black; the first three segments on the upperside very indistinctly separated ; 
the black pile scarce, bristly on the upper part; there are two dorsal spines in the middle of the 
hind margin of the first segment, a row at the hind margin of the second segment (the two middle ones 
stouter), a double row on the third segment, and a great number, mixed with black hairs, on the fourth ; 
venter in its middle portion spinose. Legs rufous, with many, though not long, bristles; hind femora at 
the underside with black hairs; claws rufous, with black tips; pulvilli pale yellow; front tarsi not 
dilated. Tegule and wings rather dark brown; small cross-vein placed before the middle of the discal 
cell; apical cross-vein incurved at its base ; posterior cross-vein undulate. 
Hab. Panama, Volcan de Chiriqui 3000 feet (Champion). 
A single female specimen. S. truncaticornis might easily be mistaken for a small 
example of S. bipartita, but it differs in many respects. 
