16 
DIPTERA. 
8. Hystricia amena. (Tab. I. fig. 11.) 
Hystricia amena, Macq. Dipt. Exot. ii. 8, p. 44. 2.° 
Hab. Mexico!; Costa Rica, Volcan de Irazu 6000 to 7000 feet (Rogers). 
A single female specimen. 
As Macquart has only described the male, I give here a full description of the 
female :— 
Head greyish-white ; face nearly vertical, a little prominent at the oral margin ; vibrisse accompanied below 
by a few other bristles, and surmounted by a single shorter one; cheeks bare; beard yellowish. Front 
dark grey, much narrowed behind; median band black; frontal bristles abundant, though but mode- 
rately long and stout, several placed close together on both sides of the base of the antenne ; occiput with 
grey pile, and with a row of short black bristles above behind the eyes. Antenne black; second joint 
bristly on its upperside ; third joint twice as long as the second, rather broad, before and behind recti- 
linear, truncate at the end; arista indistinctly jointed, thickened to beyond the middle. Proboscis testa- 
ceous, at the end with yellow pile; palpi slender, exserted, fulvous, with rather long black bristles. 
Thorax cinereous, with four narrow blackish stripes ; a spot under the shoulders and another beneath the 
root of the wings are reddish; pilosity of the upper part black and mixed with many bristles, that of the 
pleure yellow. Scutellum rufous, with a great number of black spines. Abdomen notably broader than 
the thorax ; bright fulvous, somewhat transparent, with black dorsal and lateral spots on the hind borders 
of the segments, the dorsal spots of the second and third segments round, and the lateral ones of the apical 
segment larger; the black spines are neither strong nor numerous enough to cover the ground-colour, 
only on the black spots are they more accumulated. Legs fulvous, the tibie more of a brownish-red, the 
tarsi black; front tarsi dilated; bristles of the legs rather weak, the underside of the coxe clothed with 
a long yellow pilosity ; foot-elaws fulvous, with black tips; pulvilli pale yellow. Tegule fulvous, with 
yellow pile. Wings brownish; small cross-vein placed a little before the middle of the discal cell ; 
apical and posterior cross-veins curved. Length 13 millim. 
9. Hystricia micans, sp.n., ¢ 9. (Tab. I. fig. 12.) 
Antenne black, with the basal joints rufous, the third joint as long as the second; cheeks with blackish pile; 
thorax cinereous; scutellum testaceous ; abdomen brownish-red, with black dorsal and lateral spots and 
white incisions ; legs, including the tarsi, fulvous; tegule and wings brownish. 
Length 13-15 millim. 
Face and cheeks yellowish, the latter with a blackish rather long pile; front of the male much narrowed 
behind, that of the female broader, its lateral borders yellowish-grey, the median band black. Basal 
joints of the antenne rufous; third joint black (of about the same shape as in the preceding species). 
Proboscis piceous, the end with yellow pile; palpi rather slender, very little thickened near the tip, the 
upperside with short, the underside with longer, black bristles. Thorax and scutellum as in H. amena, 
the scutellum, however, less clear; macrochete of the thorax (at least in the female) longer and more 
numerous. Abdomen brownish-red, with black dorsal and lateral spots, the incisions with a white reflec- 
tion; the spines rather more numerous than in H.amena. Legs, including the tarsi, fulvous; front tarsi 
dilated in the female; underside of the coxe with yellow pile, mixed with black bristles, that of the 
anterior femora also with yellow hairs ; for the rest the bristles of the femora and tibiae are a little stouter 
and longer than in H. amena; claws yellow, with black tips ; pulvilli pale yellow or whitish, in the male 
surrounded by some black bristles. Tegule and wings greyish-brown ; venation as in H. amena. 
Hab. Costa Rica, Rio Sucio, Volcan de Irazu 6000 to 7000 feet (Rogers). 
Three males and three females. 
