ART. 9 FLIES OF THE GENUS STYLOGASTER ALDRICH 25 



the dark pleural band extends to the middle coxae. Hind part of 

 mesonotum brownish yellow. Scutellum not very dark brown, the 

 dark color of the mesonotum limited to a triangle below the 

 scutellum. 



Abdomen mostly black, not in very good condition in the single 

 specimen, the lateral bristles of the first segment are all pale and 

 arise from a pale area; the second segment shows an unusual char- 

 acter in having the lateral bristles extending all the way along the 

 sides instead of being limited to a small area near the front of the 

 segment. 



Front and middle legs pale yellow, the hind femora yellow with 

 two ill-defined dark annuli; hind tibiae dark yellow except the 

 apical fifth, which is brown. Hind tarsi brown. Hind trochanters 

 bare and femora without noticeable pile on the inner side. 



Wing a little brownish; hind cross vein more erect than usual, 

 its anterior end almost exactly at the same distance from the base 

 of the wing as is the tip of the second vein, which is, however, nearer 

 the base than usual. 



Length, 3.8 mm. 



Described from one male, Cano Saddle, Gatun Lake, Canal Zone 

 (R. C. Shannon). 



Type.—M^lQ, Cat. No. 43033, U.S.N.M. 



STYLOGASTER PERUVIANA, new species 



Female. — Frontal triangle large, shining black, brown anteriorly, 

 its blunt apex just touching the lunule; the silver of the face ex- 

 tends up the orbits to an unusual extent, comprising almost half the 

 front outside the triangle, the intervening space being velvet black; 

 first antenna! joint dark yellow, second brown, third broadly red- 

 dish below, about one and four-tenth times the second. Mesonotum 

 shining brownish black, the white humeri only slightly bordered 

 with brownish yellow behind and mesially; posterior edge of meso- 

 notum dark brown. Mesopleura with a wide but rather short 

 brown stripe. Scutellum dark brown on disk, elsewhere light brown. 

 Metanotum with a triangular bulging portion black. Humeral 1; 

 notopleural 2; supraalar 2. 



Abdomen mostly shining brownish black; first abdominal seg- 

 ment with black bristles laterally, arising from a brownish spot; 

 second segment with irregularly arranged lateral bristles of de- 

 creasing size, becoming hairlike only at the hind edge; second to 

 fifth segments with lateral triangles of yellow, which are successively 

 smaller and more widely separated at the middle. Ovipositor as long 

 as the remainder of abdomen, its narrow basal joint yellow, the fol- 

 lowing two of almost equal length, narrowly yellowish at base, tip of 

 last segment and the median process yellow. 



