\ NEMOCHATA.—GONTA. 39 
porrected ; facial ridges without bristles; cheeks broad, with some weak pile. Antenne obliquely 
projecting; second joint elongate; third joint a little longer and broader than the second, convex on the 
front side; arista distinctly articulated. Palpi enlarged towards the end. Macrochete of the scutellum 
long, and reaching over the first two abdominal segments. Abdomen elongate-oval, convex; first 
segment abbreviated ; macrochetee of the second and third segments only at the hind margin; genitalia 
of the male conspicuous. Legs moderately long; foot-claws and pulvilli elongated in the male. Wings 
without costal spine; apical cell narrowly opened at a short distance from the tip; curvature of the fourth 
vein with an acute angle, the vein apparently prolonged by means of a fold on the surface; posterior 
cross-vein on two-thirds of the apical cell. 
From Schineria, Rond., and Demoticus, Macq., which also have a distinctly jointed 
arista, this new genus differs by the macrochete being absent from the middle of the 
second and third abdominal segments. Moreover, it is distinguished from Schineria by 
the open apical cell, and by the small cross-vein being placed at a greater distance from 
the curvature of the fourth vein; and from Demoticus by the wings not having a costal 
spine. 
a 
1. Nemocheta dissimilis, sp. n.,¢ 9. (Tab. %& figg. 18,3; 18a, head in 
profile. ) 
Shining bluish-black; in the male the abdomen laterally rufous; head ochraceous; palpi fulvous; antenne 
(except the basal joints, which are rufous) and legs black; wings grey, with yellow base, 
Length 9 millim. 
Head sericeous, pale ochraceous; front more obscure, in the male as broad as, in the female broader than, the 
eyes; median band narrow, piceous; beard and pilosity of the occiput yellowish. Antenne black, the 
basal joints more or less rufous; second joint bristly on the upper part. Proboscis black. Palpi fulvous. 
Thorax, scutellum, and abdomen shining bluish-black ; in the male the sides of the first three segments of 
the latter (and the central portion of the venter also) are broadly fulvous, somewhat transparent ; in the 
female the abdomen is unicolorous, black. Legs black. Tegule and the extreme base of the wings 
yellow, the wings for the rest with a grey tinge; small cross-vein placed on the middle of the discal 
cell; apical and posterior cross-veins scarcely curved. 
Hab. Costa Rica, Cache (Hogers). 
A male and a female specimen. 
GONTA. 
Gonia, Meigen, Iliger’s Mag. li. p. 280 (1803). 
1. Gonia pallens. 
Gonia pallens, Wiedem. Aussereur. zweifl. Ins. ii. p. 346. 6'; Macq. Dipt. Exot. ii. 8, p. 50. 4’; 
Arribélzaga, An. Soc. Cient. Argent. x. p. vill (1880 35 van der Wulp Tijdschr. voor Ent. 
XXVi. p. 23. 15%. Wrong, WoT ¢ 
Gonia chilensis, Macq. Dipt. Exot. 11. 3, p. 50. 5, t. 5. fig. 4°; Blanch. in Gay’s Historia fisica y 
polit. de Chile, Zool. vii. p. 422, Atlas, t. 4. fig. 20°. 
Gonia angusta, Macq. Dipt. Exot. ii. 3, p.51. 7, t. 5. fig. 5; Walk. List Dipt. Brit. Mus. iv. p. 798. 
Gonia lineata, Macq. Dipt. Exot., Suppl. iv. p. 178. 15. 
Hab. Mexico, Ventanas in Durango 2000 feet (Forrer).— Braziu12; Curii® §; 
ARGENTINE ReEpuBLIC? 4; Patagonta; ANTILLES, Cuba®, Jamaica. 
A single female specimen has been captured by Mr. Forrer in N. Mexico. 
