550 TERTIARY INSEOTS OP NORTH AMERICA. 



abdomen indicates that it is a female. The wings are uniformly faint 

 fuliginous, but probably hyaline in life, covered with microscopic hairs 

 over both membrane and veins ; they are short and broad and well rounded; 

 the veins in the upper half of the wing are rather darker than those in the 

 lower; the costal vein is bristly and extends to the tip of the fourth longi- 

 tudinal vein ; the stout first longitudinal vein strikes the costal at the middle 

 of the front margin ; the auxiliary vein appears to be confluent with the 

 first longitudinal vein half-way from the base of the wing to the tip of the 

 former; then, rapidly curving forward, diverges from it, and at its tip is as 

 distant from the first longitudinal vein as the second longitudinal is from 

 the third above the short transverse vein ; the transverse shoulder vein is 

 slightly curved and a little oblique and lies directly above the base of the 

 small basal cells ; the direction and relation of the longitudinal ^eins is the 

 same as in A. inanimata, but the small transverse vein lies slightly beyond 

 the middle of the wing, so that the divergence or parallelism of the veins is 

 more marked than there ; the large transverse vein is bent slightly inward 

 in the middle, and its general direction is about midway between perpen- 

 dicular to the costa and parallel to the neighboring border ; its lower 

 extremity is but half as far from the margin of the wing as its own length ; 

 its upper divides, a little before the middle, the portion of the fourth longi- 

 tudinal vein which lies beyond the small transverse vein, but instead of 

 being only half as long as the portion of the fourth longitudinal vein lying 

 between the two transverse veins, as in A. inanimata, it is very nearly as 

 long; the fifth longitudinal vein just fails of reaching the border, while the 

 sixth only runs about two-thirds the distance to the border; the basal cells 

 are moderately large, much as in tha preceding species. On one side there 

 are apparently remains of tegulse, showing that the insect should be 

 referred to this group of Muscidse. The apical third of the hind tibia is fur- 

 nished abundantly with not very long hairs, while the remainder of the 

 tibia is bare. 



Length of body, 4.75 mm ; length of wing, 4.75"" 11 ; breadth of same, 

 !>"""; length of hind tibia', 1.15 ram ; length of hind tarsi, 1.2. r > inm . 



Named for my friend Mr. Edward Burgess, whose critical knowledge 

 of Diptera, before he turned his attention exclusively to naval architecture, 

 was of the greatest service to me. 



Quesnel, British Columbia. One specimen, No. 29 (Dr. Gr. M. Dawson, 

 C4eologic;il Survey of Canada). 



