120 THE CANADIAN ENTOMOLOGIST. 



slightly longer than the second, the third one and three-fourth times as 

 long as the first two taken together, of nearly an equal width, the style 

 nearly half as long as the third joint. Thorax marked with a broad 

 median black stripe not extending on the posterior fourth, and on each 

 side of it is a large brown pollinose spot divided by the suture and 

 bounded in front by a black spot, also a brown spot on the humeri, 

 elsewhere the pollen is grayish-white, the pile very sparse, white, the 

 bristles brown ; pleura brown pollinose in front, grayish-white pollinose 

 behind, the fan-like row ol hairs in front of the halteres white. Scutellum 

 brown pollinose, a black spot at the base each side ; bearing two brown 

 bristles. Abdomen smooth, sparse grayish-black pollinose, that at base 

 and sides of segments two to four gray, the fifth and sixth segments 

 wholly silvery pollinose ; second segment longer than wide, the others 

 wider than long, the fifth being two and a-half times as wide 

 as long ; venter gray pollinose and with a median brown pollinose 

 stripe, its pile and that of the legs white, the bristles of the 

 latter white and yellowish ; posterior tibiae within, and the underside of 

 their tarsi, densely silvery-white pollinose and pubescent. Wings hyaline, 

 an indefinite pale brown spot extends from the tip of the auxiliary vein 

 to the base of the fifth posterior cell, darkest in the marginal and inter- 

 rupted in the first submarginal cell; a second brown spot covers the veins 

 at bases of the first, second and third posterior cells ; a scarcely apparent 

 brown spot at base of second submarginal cell, and a large one filling 

 apices of the marginal, first and second submarginal and of the first 

 posterior cell, extending from one-half to three-fourths the distance from 

 the tip to the base of the second submarginal cell, and sometimes con- 

 nected with the first mentioned brown spot by a. brown streak extending 

 through the middle of the marginal cell ; all posterior cells open, the 

 anal cell closed. 



$ . — Same as the $ , except that the apices of the fifth and sixth 

 abdominal segments are never red, the pollen covering these segments is 

 never silvery, and the posterior tibiae and tarsi are destitute of silvery 

 pollen and pubescence. 



Length, 8 to 10 mm. Los Angeles and San Bernardino Counties, Cal. 

 Nine males and eight females in April. 



