62 Psyche [April 



Abdomen concolorous with thorax, glaucous on the sides to a little above the suture; 

 hairs black above, pale on the glaucous portion; male appendages much retracted 

 in drying, as usual. Front coxse with abundant yellow hairs on fore side and no 

 black spines at all; front femora only moderately robust, with yellow hair on 

 inner side, long toward the apex in male; underneath at base outside the flexed 

 tibia with four (male) to seven (female) smallish spines of increasing length distally; 

 fore tibiae almost straight, with a row of slender short spines on flexor side, stronger 

 distally. Wings indistinctly brownish with the two dots plainly visible to the 

 naked eye; none of the veins yellow. Length of male, 4 mm.; of female, 3.9 mm. 



Redescribed from cotypes, one male and one female, collected 

 by Wheeler at Two-Gwo-Tee-e Pass, Wyo., Sept. 12, 1895. The 

 specimens were loaned to me for study by the American Museum 

 of Natural history. 



I have seen no more material in this species. It differs from 

 chrysologus in ha^dng fewer spines on the under side of the front 

 femur. Chrysologus is mostly eastern, but I have one male from 

 Boulder, Colo. 



Hydrophorus chrysologus Walker. 



Male. Occiput, front, face and palpi wholly seal-brown poUinose, opaque; 

 postorbitals one pair, postverticals about twelve in number on a side, extending 

 down more than halfway behind the eye, beard deep yellow, abundant; cheek very 

 narrow; palpi with brown hairs; antennae rather small, with no unusual features. 

 Thorax and abdomen deep brown above, somewhat shining; this color extends 

 down on the pleura a short distance, and correspondingly on the abdomen, below 

 glaucous. In one of the two males the abdomen is distinctly more greenish. Scu- 

 tellar bristles two pairs, humeral two, notopleural two; dorsocentrals much smaller 

 than in pirata, acrostichals minute; propleura with stout yellow hairs and one black 

 bristle; remainder of pleura bare except a few microscopic hairs on the mesopleura; 

 squama brown with yellow hairs; halteres brown, the middle of the stem yellowish. 

 Front coxse j'ellowish pollinose on the inner half of the front side, the rest some- 

 what glaucous, a row of small black spines running up the front outside the middle 

 line; these spines are scattering and irregular; front femora not much thickened, 

 below with two irregular rows of spines of uneven size and between the rows some 

 minute setules; tibia straight, with a row of short rather inclined spines on the flexor 

 side as usual, not ending with a longer spine; the other femora not especially slender 

 nor elongated for this genus. Wings narrow, with black veins, almost hyaline 

 with distinct spot on hind crossvein and another beyond it on the middle of the last 

 segment of the fourth vein; these two spots can be seen with the naked eye against 

 a white background. Fourth segment of the abdomen with a V-shaped projection 

 below, more conspicuous in a shriveled specimen than in a normal one; the latter 

 has two long lamellae hanging down near apex, which are folded in in the other speci- 

 men, so the hypopygium does not look like the same structure in the two specimens. 

 Length, 3 mm.; of wing, 3.5 mm. 



