DEXIOSOM4A.—MACROMETOPA. 245 
. Bigot has described two species of this genus, both from Mexico :— 
Dexiosoma fumipenne, Bigot, Ann. Soc. Ent. Fr. 1888, p. 270. no. 84. 
partitum, Bigot, l.c. no. 85. 4 
The author has been kind enough to send me the typical examples of these species 
for examination :— 
The first mentioned does not possess the generic characters of Dexiosoma; see my 
annotations under Rhynchodewia fraterna, p. 230. 
D. partitum, on the contrary, seems to be a true Dexiosoma; the typical specimen, 
however, is in too bad a state of preservation to be more amply described, but I 
can state that it belongs to quite a different species from D. vibrissatum. 
MACROMETOPA. 
Macrometopa, Brauer & v. Bergenstamm, Denkschr. der kais. Akad. der Wissensch. Wien, lvi. 
p. 117 (1889). 
Front convex and prominent, in the male narrowed behind; face convex, carinated ; cheeks broad, their 
lower portion exceeding the longitudinal diameter of the eyes; vibrissal swellings parallel, disunited from 
the antennal grooves; oral cavity elevated, its margin with a row of bristles ; vibrisse inserted 
considerably above the oral margin, not longer than the other bristles on the facial ridges; eyes small, 
bare. Antenne very short, inserted beneath a line drawn through the centre of the eyes ; third joint as 
long as the second ; arista with short hairs. Proboscis shorter than the head, with distinct terminal lips ; 
palpi thickened and with long bristly hairs on the tip. Abdomen elongate-oval, convex, with discal and 
marginal macrochete. Legs robust, with many hairs and bristles; tarsi scarcely longer than the tibie ; 
foot-claws and pulvilli elongate in the male. Wings longer than the abdomen ; apical cell opened at 
gome distance before the wing’s tip; curvature of the fourth vein somewhat rounded and descending 
towards the posterior margin of the wing, without appendage. 
1. Macrometopa calogaster. (Tab. V. figg. 14; 14a, head.) 
Microphthalma calogaster, Bigot, Ann. Soc. Ent. Fr. 1888, p. 266. no. 66. 
Macrometopa mexicana, Brauer & v. Bergenst. Denkschr. der kais. Akad. der Wissensch. Wien, 
lvi. p. 166. 
Blackish ; thorax with obsolete black stripes ; abdomen testaceous, with a black dorsal band; palpi and base 
of the antenne rufous. 
Length 11:5 millim. . 
Frontal band black, broader than the lateral portions ; on the vertex a white point; face and cheeks grey, 
with brownish reflections; on the cheeks some fine and weak hairs. Antenne rufous, the second joint 
prominent and with some hairs ; the third joint, except its base, black; arista black, thickened at the 
base and with short hairs. Proboscis black; palpi rufous. Thorax and scutellum black: thoracic 
dorsum anteriorly with some grey tomentum and indistinct black stripes. Abdomen with a broad black 
dorsal band, laterally testaceous with grey reflections ; second and following segments with many discal 
and marginal macrochete. Legs black, the hind tibize piceous ; front femora with a row of bristles on 
the upper- and undersides ; middle and hind femora with bristles on the underside; middle and hind 
tibiee with several rather long bristles ; foot-claws and pulvilli elongate in the male, the pulvilli blackish, 
Tegule and wings brownish-hyaline ; small cross-vein oblique, nearly on the middle of the discal cell ; 
posterior cross-vein distinctly undulate. 
