220 DIPTERA. 
2. Hystrichodexia formidabilis. (Tab. V. figg. 4; 4a, head.) 
Rhamphinina formidabilis, Bigot, Aun. Soc. Ent. Fr. 1888, p. 264. no. 58. 
Thorax greyish-black, with indistinct stripes; scutellum piceous; abdomen yellowish-rufous, with black 
dorsal spots and blackish apex, the dark parts densely beset with strong macrochete ; legs black, the 
tibie piceous ; tegule and wings brownish. 
Length 16°5 millim. 
d. Head cinereous, the oral margin and the inferior part of the cheeks with a brown reflection ; front much 
narrowed behind, forming an oblong triangle ; frontal band brownish-black ; cheeks bare, their lower 
portion a little shorter than the longitudinal diameter of the eyes; beneath the vibrisse many shorter 
bristles along the oral margin; posterior orbits of the eyes with bristly hairs, which become longer 
behind the vertex. Antenne short, inserted below a line drawn through the centre of the eyes; basal 
joints rufous; second joint prominent, with a rather long and some shorter bristles ; third joint brownish, 
scarcely longer than the second; arista thickened to its proximal half. Proboscis a little longer than the 
head, shining black, with the terminal lips rufous; palpi rufous, with long hairs towards the tip. Thorax 
blackish, anteriorly with some grey tomentum and obsolete black lines; scutellum piceous or even dark 
rufous, convex, densely covered with erect hairs, and with several long macrochete on the hind margin. 
Abdomen convex, yellowish-rufous, slightly transparent ; black spots are on the first, second, and third 
segments and form an interrupted dorsal stripe; the hind border of the third segment at the sides and 
the anal segment, except its anterior margin, are brown; the dark portions are densely beset and 
surrounded with strong macrochet ; similar macrochete are also on the sides, and there are many on 
the anal segment. Legs long and slender, black, the tibia brownish or dark rufous; front femora with 
a regular row of long bristly hairs on the upperside and a second row on the underside; middle and 
hind femora with bristles on the underside only ; tibiee with some bristles, those on the hind pair (which 
are slightly curved) the longest ; foot-claws and pulvilli elongate and yellow, the claws with a black tip. 
Tegule and wings brownish ; small cross-vein on the middle of the discal cell; curvature of the fourth 
vein somewhat rounded and not far from the wing’s margin; apical cross-vein concave ; posterior cross- 
vein curved. 
Hab. Mexico (coll. Bigot), Paso del Macho (Hoge) ; Nicaragua, Chontales (Janson). 
A somewhat damaged male example from each of these localities. 
They fully agree with a better preserved typical specimen (likewise a male), which 
M. Bigot has kindly sent me for examination, and from which the description and 
figures are made. 
Owing to the strong macrochete of the abdomen, the species seems to be best 
placed in the genus Hystrichodexia. 
3. Hystrichodexia echinata, sp. n., ¢. 
Black ; thoracic dorsum anteriorly whitish-grey, with black stripes ; antenne and palpi rufous; curvature of 
the fourth vein angular. 
Length 12 millim. 
Head dark grey, the median portion of the face whitish; front a little broader than the eyes ; frontal band 
dark rufous ; cheeks bare, broad, their lower part and the oral margin rufous, the former as long as the 
longitudinal diameter of the eyes; oral margin with bristles. Antenne, including the arista, rufous ; 
second joint with some short bristles and a longer one; third joint scarcely longer than the second, its tip 
not fully reaching half the face; arista rather thick, moderately long-plumose. Proboscis black, a little 
longer than the head, the terminal lips distinct and brownish ; palpi rufous, the tip not thicker, with 
some long bristly hairs. Thorax and scutellum black; thoracic dorsum anteriorly whitish-grey, with 
several rather indistinct black stripes. Abdomen black, densely beset with spinose macrochete. Legs 
black, the tibiee with scattered bristles ; foot-claws and pulvilli short. Tegule and wings brownish : 
