ALDRKJH AND DARLINGTON, 97 



Heloinyza distigma Van der Wulp; 



''Eiifo-testaceoiis ; aiiteiinse and legs rufous; two rounded spots in the first 

 posterior cell, in addition to the other blackish markings on the wings. 



" Length 5-7 mm. 



"Male. — Head pale rufous; front much broader than the eyes; ocellar point 

 shining brown, emitting two bristles, which are curved forward ; exterior to 

 these are two other bristles, and on each side of the vertex a pair of post-vertical 

 bristles; face and cheeks broad ; two weak vibrissse at the oral margin. Antennae 

 rufous, short; third joint rounded; arista black, nearly bare. Proboscis and 

 palpi rufous. Thorax and scutelluni testaceous; thoracic dorsum with numerous 

 hair-points; pleurae with a brown stripe from the shoulders to beneath the base 

 of the wings; the sides of the thorax with some bristles; scutelluni with four 

 bristles — one on each side and two at the hind margin; nietanotum rufous. 

 Abdomen grayish-brown, the anal segment globular and more rufous; the seg- 

 ments with some marginal and lateral bristles. Legs rufous, tips of the tibiae, 

 and the last three joints of the tarsi blackish ; hind tibiae with an indistinct 

 brown ring near the base; femora rather robust, hairy beneath, the first and 

 third pairs each with a row of bristles on the upper side; tibiae with a preapical 

 bristle. Halteres pale rufous. Wings grayish, with a row of short costal bris- 

 tles, and with a blackish costal border, covering the mediastinal cell and from 

 there extending to the tip of the wing, where it becomes narrower, to the end of 

 the fourth vein ; the cross-veins bordered with black; a spot on the fourth vein 

 beyond the posterior cross-vein, a rounded dot between the second and third 

 veins, just above the small cross-vein, and two similar spots between the third 

 and fourth veins. Small cross-vein a little beyond the end of the lirst vein and 

 beyond the middle of the discal cell; posterior cross-vein stiaight and slightly 

 oblique. 



"Female. — Diffeis from the male in having the abdomen pointed towards the 

 apex, the arista shortly plumose, and the legs more slender and less hairy; the 

 femora have a brown spot on the upper side near the tip, and the tibiae dark 

 rings near the base; the markings of the wings are similar, only the blackish 

 dot between the second and third veins is wanting. 



"Hab. Mexico, Amula, 6000 ft. ; Xucunianatlaii, 7000 ft. ; and 

 Sierra de las Aguas Escondidas, 9500 ft., all in Guerrero (H. H. 

 Smith)." 



Heloniyza poIy$«fignia Van der Wulp. 



"Testaceous; a blackish stripe on the pleurae; wings with a blackish border to 

 the costa and to the cross-veins, and numerous spots in all the cells. Leno-tli 

 4.5 mm. 



"Allied to the preceding species [di.siigma], but smaller and differing from it in 

 the markings of the wings. Face, cheeks, and anterior portion of the front yel- 

 lowish, with a white reflection; front posteriorly rufous, with some brown 

 points; frontal bristles as in H. disiigma ; a black spot on each side between the 

 orbits and the root of the antennae. Antennae rufous; third joint rounded, 

 blackish on the upper side; arista with very short hairs. Proboscis lufous (the 

 palpi inconspicuous in the specimens examined). Thorax and scutellum brown- 

 ish testaceous, the shoulders yellowish, beneath them on the partly cinereous 

 pleurae a blackish stripe; scutellum with four bristles. Abdomen brown the 

 segments with narrow black borders. Femora blackish ; tibiie rufous, with black 



TRANS. AM. ENT. SOC. XXXIV. (13) MAKCH. 1908. 



