357 



Eyes separated bv slightly less than one third the head-width, orbits 

 each about half as wide as central stripe at its narrowest point ; decus- 

 sate frontal bristles slender. Abdomen much broader than in male. 

 Legs stouter than in male ; mid femora with a stout bristle about one 

 fourth from base on the antero-ventral surface which is appreciably 

 shorter than the diameter of the femur (in dpi cola this bristle is more 

 slender and much longer than the diameter of the femur). Third and 

 fourth wing-veins slightly convergent apically. 



Length, 5.5-7 mm. 



Type locahty, Algonquin (Nason). 



The type series consists of one male and three females, two bear- 

 ing Algonquin labels (one with the date May 24, 1895), and two 

 laJDcled N. 111., one of the latter also bearing Stein's hxhd "Pogono- 

 myia n. sp.", and presumably the species referred to by him in Berliner 

 Entomologische Zeitschrift*. Subsequently Stein referred to the 

 species a specimen from Wisconsin, but as he had only seen females 

 he did not describe the species. 



The foregoing description should serve to separate alpicola Ron- 

 dani, and flavinervis. I have not seen aterrima Van der Wulp, which 

 was described from Mexico, but it must be very similar to alpicola if 

 not identical with it. I have both sexes of alpicola from Moscow, 

 Idaho, May 22, 191 3 (J. M. Aldrich). 



GEOMYZID^ 



Aphaniosoma ouadrivittatum, n. sp. 



Female. — Opaque yellow. Head yellow with the exception of a 

 small spot surrounding the ocelli and a small area round the connection 

 l)etween the head and thorax, which are black ; eyes iridescent green 

 in life. Mesonotum with four blackish gray vittse, the center pair in- 

 distinctly connected with a similarly colored spot on center of anterior 

 margin at connection of head and thorax, lateral pair discontinued at 

 humeri, posteriorly all four vittae being discontinued slightly beyond 

 middle of disc, the lateral pair slightly exceeding the median pair in 

 length; lower portion of sternopleura slightly darkened; postnotum 

 blackened on low^er half. Abdomen pale yellow, each segment with a 

 conspicuous blackish brown cross-band on basal portion which is broad 

 on median line and narrows towards each lateral margin. Legs yellow. 

 Wings clear, veins yellow. Halteres yellow. Bristles on head and 

 thorax black, surface hairs yellow. 



*V^ol. 42, 1897, p. 170. 



