AMERICAN DIPTERA. 263 



with the geminate stripe. The bloom between the scutellum and the 

 abbreviated geminate stripe is more nearly white. Posterior angles 

 of the humeri red. Dorsum everywhere with short, erect black pile 

 with a few black bristles on the sides; scutellum with similar but 

 longer pile. Pleurse polished black, the mesopleura and a small area 

 over the posterior coxse yellowish-brown pruinose; trichostical hairs 

 and a patch of pile on the mesopleura before the mesopleural groove 

 black. Halteres pale yellow. Abdomen polished blue-black; pos- 

 terior lateral margins of segments 2-5 white pruinose. Sides of all 

 the segments with pale yellow, almost white, pile, which is long and 

 tufted on the first three segments, but not as noticeable on the follow- 

 ing segments. Hypopygium black. Femora wholly black; tibiae and 

 tarsi dark chestnut; the tibiae and tarsal segments black distally. Pile 

 of legs almost wholly black excepting numerous pale yellow hairs on 

 the femora, especially below, and a dense array of short appressed 

 golden ones on the inner side of the fore tibia? and tarsi, and on the 

 distal portion of the hind tibiae and their first two tarsal segments. 

 Wings hyaline, with two brown spots; one on the outer third of the 

 wing, the other smaller, occupying the distal half of the anal cell and 

 running over into the adjoining cells. 



9 . — The female does not differ from the male except in the absence 

 of the spots on the wings. The wings are not hyaline, however, but 

 are more or less darkened on the outer half, and about the anterior 

 cross- vein and the anal cell. 



Type. — British Museum. There are at the M. C. Z. four 

 males and four females, five of which are in the collection of 

 Osten Sacken and three in that of Loew. 



Habitat. — N. A. (Walker) ; White Mts., and Mt. Washington, 

 N. H. (Osten Sacken) : top of Las Vegas Range, N. M. (June 

 28) ; Lower Minn. 



Description made from the M. C. Z. material. In the col- 

 lection of the Am. Ent. Soc. of Phila. there are four male and 

 two female specimens from the top of the Las Vegas Range, 

 N. M., which agree in every respect with the White Mountain 

 specimens; an interesting case of geographical distribution. 



Cyrtopog'on falto. 



Dasypogon falto Walker, List, II, 355, 1849. 

 Cyrtopogon chrysopogon Loew, Cent., VII, 55,, 1866. 

 Dasypogon falto Walker, Can. Ent. Ill, 142, 1871 (oc. in Nova 



Scotia) . 

 Dasypogon falto Osten Sacken, Cat., 1878, 69 (is falto same as 



chrysopogon?) . 

 Cyrtopogon chyrsopogon Howard, Insect Book, 1902, PI. XIX, 



fig. 28. 



TRANS. AM. ENT. SOC., XXXV. ' JULY, 1909 



