302 DIPTERA FROM SOUTHWESTERN UNITED STATES 



Pegomyia afiSnis Stein 



1897. Pegomijia affinis Stein, Berl. Ent. Zeit., xliii, 286. 



This species is usually found in caves or in holes in the ground 

 frequented by mammals. In the collection there are six males 

 and three females with the following data: Grizzly Peak, Berke- 

 ley Hills, California, March 24, 1908; Berkeley Hills, April 11, 

 1908; November 19, 1908, (? C. Fuchs); Alamogordo, New Mex- 

 ico, April 3^ and May 8, 1902. 



This species is the only one in the subfamily known to me that 

 has bristles at base of the third vein. These bristles are very 

 weak, and sometimes absent. 



Pegomyia minuta sp. n. 



Male. — Head yello\\-ish testaceous; occiput gray, densely gray pruinose; 

 face and facial orbits densely white pruinose, most noticeable when seen from 

 in front ; third antennal joint entirely black; arista black at base; palpi yellow. 

 Thorax fuscous or brownish, densely gray pruinose, not vittate. Abdomen 

 clay colored, apices of segments paler, each dorsal segment with a dark spot 

 at base in center which does not extend to apex of segment; the hairs and bristles 

 each with base surrounded by a black or brown dot; fifth sternite yellowish. 

 Legs yellowish testaceous, the femora browTiish on middle. Wings clear. 

 Calyptra and hal teres whitish. 



Head large, in profile with frons slightly protuberant anteriorly; eyes 

 separated by width across posterior ocelli; orbital bristles not carried to ocellar 

 triangle; antennae not reaching beyond two-thirds of distance to mouth 

 margin; third joint slender, not twice as long as second; arista nearly bare, 

 third joint distinctly swollen at base for about twice the length of second 

 joint; parafacial in profile nearly as wide as third antennal joint and half as 

 wide as height of cheek, the latter about one-fourth as high as eye, with a single 

 series of weak, black marginal bristles. Presutural acrostichals short and stout, 

 four to five pairs; prealar bristle absent. Abdomen narrow, slightly depressed; 

 processes of fifth sternite narrow, glossy, their apices rounded, surfaces with 

 weak hairs except on apical third. Fore tibia with one weak posterior setula; 

 mid tibia with one postero-dorsal and two posterior short bristles; antero- 

 ventral surface of hind femur with a few widely placed short bristles; hind 

 tibia with one antero-ventral, three antero-dorsal, and two postero-dorsal 

 bristles. Costal thorn very minute; outer cross-vein almost straight; third 

 vein ending in wing tip. Length, 4 mm. 



Type.— d^ ; Alamogordo, New Mexico, April 14, 1902, [A. N. S. 

 No. 6212]. 



This species is closely allied in ruficeps Stein and ntfescens Stein. 

 From both of these species it may be separated by the entirely 

 black third antennal joint and the shape of the processes of the 

 fifth abdominal sternite. 



