81 



the terminal segments visible from above because of the upturning of the apical 

 segments. 



Holotype. — $?, Mount Washington, New Hampshire, 2,500 ft., June 13, 1916, 

 collected by C. W. Johnson; in the Museum of the Boston Society of Natural 

 History. 



This species cannot be confused with any described species on 

 account of the truncate abdomen and absence of pale fasciae. Its 

 only ally is Syrphus transversalis Curran, which has bare eyes, 

 yellow abdominal fasciae and never more than a slight brown dash 

 on the upper portion of the facial tubercle. The $ will be difficult 

 to associate, although the terminal segments should be more or 

 less deformed in appearance, if it is similar to $ transversalis. 



Chilosinae. 



Pipiza nigro tibia ta, sp. nov. 



Figs. 1 and 2. 



Allied to Pipiza femoralis Lw., especially var. albipilosa Williston, but the 

 posterior tibiae are almost all long black pilose, the whole insect is darker and 

 the pile longer. The $ has no pale abdominal fascia. 



Male. — Length, 8.5 to 9.5 mm. Face moderately retreating, scarcely pro- 

 duced below, gray pollinose, black pilose with the sides and upper hah of the 

 front pale-haired or all pale-haired, the hair rather long and abundant. Front 

 similarly pollinose to face except immediately above the antennae. Vertical 

 triangle pale-haired, several black hairs in front and a few scattered elsewhere; 

 occiput grayish pollinose and pale-haired, the occipital ciliae black. Eyes with 

 black or brown hair which becomes yellowish and white on the lower edge. 

 Antennae black, the apex of the second and broad base of third segments often 

 brownish red; third joint elongate-subcordate, more cut off above; arista longer 

 than the third joint, thick on basal half, distinctly micropubescent to tip, 

 brownish red in color, the apical third brown (Fig. 1). 



Thorax and abdomen blue black, densely punctured, white pilose, the former 

 with scattered black hairs before the suture, which may sometimes be very 

 numerous, especially along the sides and often on the posterior and upper 

 margin of the mesopleura. The scutellum lacks an apical groove and bears 

 only a few black hairs or none. 



Legs black; apices of femora, basal sixth and apex of tibiae, first three joints 

 of front four tarsi, although the third joint may be darker, reddish yellow, the 

 broad apex of the first joint of the hind tarsi and the whole of the second joint 

 brownish red. Pile of legs moderately long, whitish, the posterior tibiae with 

 long black hair except on the antero-ventral surface and anterior surface at 

 apex. Posterior femora rather robust, strongly angulate at apex. They are 

 larger than in Pipiza femoralis Lw. but decidedly smaller than in grandi- 

 femoralis Curran (Fig. 2). 



Wings cinereous hyaline, usually strongly tinged with brown on apical half, 

 especially toward the front. Venation as in femoralis. 



Abdomen with the usual sub-opacme areas, the pile longish and the black 

 pile much more conspicuous than in allied species. Genitalia normally all 

 black-haired. 



Female. — Front moderately narrowed above; in the middle with broadly 

 separated, large, roundedly triangular gray pollinose orbital spots, connected 

 along the eyes with the facial pollen. Frontal pile almost white, with con- 

 spicuous black hairs just above the antennae and a very narrow.fascia across 

 the ocelli. 



