296 SUPPLEMENT. 



antennae; palpi slender, single-jointed. Antennae about as long as the distance from their base to 

 the ocelli, which are situated at the vertex ; first joint stout, about three times as long as the second ; 

 second joint about as long as broad ; third of nearly the same length as the first and but little broader, 

 not tapering, with short black hair and a minute style. Thorax with black bristles before the root of 

 the wing, on the posterior part of the mesonotum, and on the margin of the scutellum ; nearly bare of pile. 

 Abdomen elongate, cylindrical, with nearly parallel sides, not broader than the thorax, composed of seven 

 segments, bare of pile, except on the sides of the first segment ; with bristles on the hind margin of the 

 segments. Wings narrow, markedly wedge-shaped at the base, the alulae wholly wanting ; anal and 

 axillary cell narrow ; origin of the second vein before the base of the discal cell ; marginal cell dilated 

 at the extremity, the second vein joining the costa at nearly a right angle ; two submarginal cells, four 

 posterior cells ; all the cells open. All the tibiae with bristles ; pulvilli well-developed. 



In the shape of the wings and the venation, this genus somewhat resembles Scinaw, 

 and in the elongate bristly body, Thlipsomyza. It is perhaps best placed near 

 Eclimus. 



l. Sphenoidoptera varipennis, sp. n. (Tab. v. fig. 10, $ .) 



$ . Black, the distal part of the tibiae and the basal joints of the tarsi reddish. Front opaque, and with long 

 black hairs ; face shining. Mesonotum opaque, with white tomentum. Pleurae whitish-pollinose ; 

 mesopleurae with a longitudinal row of short white hairs, above which there are scattered longer black 

 hairs, the portion below them being bare. Abdomen moderately shining ; first segment with a tuft of white 

 hair on either side ; remaining segments with black and white tomentum ; hairs at the tip black. 

 Wings hyaline and brown ; the costal border is brown as far as the tip of the first vein, including the 

 marginal cell ; from the extremity a brown band extends back to the fourth posterior cell over the cross- 

 veins ; proximally, another projection extends to the anal cell over the base of the fourth posterior cell, 

 between which and the basal brown colour there is a narrow hyaline band reaching to the first vein and 

 to the axillary cell, the latter being hyaline ; a brown spot over the base of the second posterior cell, the 

 furcation of the third vein, the tip of the second and anterior branch of the third veins, and a minute 

 one on a small stump of the second vein in the dilated part of the marginal cell. Length 6 millim. 



Hab. Mexico, Chilpancingo in Guerrero (H. H. Smith). 

 Two specimens. 



AMPHICOSMUS. 



Amphicosmus, Coquillett, Western American Scientist, vii. p. 220 (1891). 



1. Amphicosmus cincturus, sp. n. (Tab. V. figg. 11, 11 a, s .) 



S . Eyes narrowly separated above, behind the ocelli, which are situated far forward ; the narrow front forms 

 a rounded ridge. The front above and the frontal triangle black, greyish-dusted, the triangle with erect, 

 short, black hair. Face protruding conically forward, the conical portion shining black, the sides 

 whitish-pubescent. Proboscis protruding as far forward as the tip of the antennae. Antennae short ; 

 first two joints thickened, of equal length ; third joint slender, a little longer than the first two together, 

 pointed ; all the joints black. Mentum yellowish. Thorax deep black, shining, the mesonotum with 

 erect, soft, whitish pile. Abdomen black, shining, bare, contracted at the distal end of the second 

 segment, thence cylindrical, with the distal portion a little thickened ; second and third segments with 

 the narrow hind margin yellow. Legs black, wholly without bristles ; the femora with soft, short, white 

 pile. Wings nearly hyaline, the veins at the base yellow; distal end of the marginal cell dilated ; three 

 submarginal cells present. Pulvilli present. Length 12 millim. 



Hab. Mexico, Venta de Zopilote in Guerrero (H. H. Smith). 

 One specimen. 



