ALDRK'H AND DARLINGTON. 07 



Heloiiiyza diiiiti^ina Van dev Wulp. 



"Eufo-testaceoiis; anteimse 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.— H.ea,d 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 vibrissa; at the oral margin. Antenna- 

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

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

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

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

 bristles— one on each side and two at the hind margin; metanotum 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 

 l)ey()nd 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 first vein and 

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

 oblique. 



"Female. — Differs 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. 



"Hub. Mexico, Aiinila, GOOO ft. ; Xucunumatlan, 7000 ft. ; and 

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

 Smith)." 



llcloniyza polystignia Van der Wulp. 



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

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

 4.5 mm. 



"Allied to the preceding species [di.'itigma]. but smaller and differing from il 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. di.'iiifima ; a black spot on each side between the 

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

 blackish on the upper side; arista with very short haiis. Piolioscis rufous (the 

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

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

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

 segments with narrow black borders. Femora blackish ; tibia- rufous, with black 



TRANS. AM. KNT. SOC. XXXIV. (13) .MARCH. 190S 



