ART. 16. NORTH AMERICAN SCELLUS GREENE. 1 5 



bronze color with whitish dust; the fore coxae have, besides the pale, 

 and, on account of its shortness and delicacy, almost imperceptible 

 pubescence, quite a number of black bristles. Feet black, the femora 

 with a more coppery, the tibiae with a more metallic-greenish, tinge. 

 Fore femora rather strongly thickened toward the basis, on the under 

 side with strong black bristles of different length, on the front side 

 only with an imperfect row of short black bristles. Middle femora 

 moderately thickened and strongly curved, on the under side of the 

 basis with two or three not very long, on the apical half with a large 

 number of long, straight and erect bristlelike black hairs. Hind 

 femora plain, of middling stoutness, on the under side with bristle- 

 like short hairs ; on the upper side with two longer black bristles, of 

 which the larger is not far from its tip. Fore tibiae strong, with a 

 large and sharp thorn on the front side, not far from the basis; 

 elongated at the tip into a large clumsy tooth; the under side of the 

 tibia, provided with bristles, has no distinct excision before this 

 tooth. Middle tibiae long, straight, a little stronger in the neighbor- 

 hood of the basis: the first two-thirds of their under and posterior 

 side are fringed with long curly black hairs, the end of the under 

 and front side, however, with long and stiff black bristles; on the 

 under side, where these bristles begin, there is between them a some- 

 what curved black thorn. Hind tibiae straight, on the under side 

 with short but very strong black bristles, one of w^hich, being not far 

 from the tip, is remarkable for its greater length: on the outside 

 of the tip of the tibiae a few shorter and one somewhat longer curved 

 bristle are inserted. Tarsi plain, their joints of decreasing length; 

 the first joint of the fore and middle tarsi on the under side with 

 black bristles, which are of considerable length near the basis of the 

 tarsi, but decrease in length very rapidly so as to be very short on the 

 larger portion of the joint; the under side of the first joint of the 

 hind tarsi is everywhere beset with short black bristles. Halteres 

 pale-yellowish, but the basis of the knob somewhat brownish. Wings 

 hyaline; almost the whole basal third appears somewhat whitish when 

 seen in a certain direction; grayish stripes along the second half 

 of the second and third longitudinal veins, likewise along the tip of 

 the last segment of the fourth and the greater portion of the fifth 

 longitudinal vein ; there is also a gray streak between the third and 

 fourth longitudinal veins ; upon the posterior transverse vein there is 

 a blackish-gray double spot, and upon the middle of the last segment 

 of the fourth longitudinal vein there is a larger rounded blackish- 

 gray spot, which is less sharply defined on the side turned toward 

 the tip of the wing." 



Habitat. — Fort Resolution, Hudson Bay Territory (Kennicott). 



Type locality. — Fort Resolution, Hudson Bay Territory (Ken- 

 nicott). 



45554— 25— Prce.N.M.vol.65 31 



