582 GEOLOGICAL SUEVEY OF THE TEEEITOEIES. 



base ; the hind border of the occiput straight. Prothorax short, hiud- 

 margin deeply notched, nearly bilobed, pale, shining; thorax thick, pale, 

 shining on the middle denuded parts. Abdomen stout, dull-yellowish 

 above, with black oblique spots on each side of the segments, and some 

 finer lines on the ventral side. The described parts, except the anten- 

 nae, are out of the nymph-skin belonging to the imago. Abdomen of 

 the subimago pale, last dorsal segment with a small median projection ; 

 setoe strong, faintly pilose, long, grayish-brown ; a large mass of eggs 

 is protruded, but the parts are not in good condition ; feet pale, grayish- 

 brown, well developed, tarsi five-jointed ; anterior wings large, opaque, 

 pale yellowish-gray; the lougitudinal veins yellowish, the transversals 

 brown, somewhat fumose ; hind-wings more yellowish, the apical border 

 larger, grayish; reticulation similar to Ephemera. 



Length, 14 millimeters; alar eximnsion, 42 millimeters; setee, about 

 30 millimeters. 



Habitat. — Washington (Osten Sackeu) ; foot-hills, Colorado, August 

 (Carpenter). Both female subimagos, and both in very poor condition. 



In the type of the species, the femur, on the (only present) anterior 

 foot, with a dark-brown ring in the middle. 



LEPLOPHLEBIA. 



L. pallipes, sp. no v. 



Female imago. — Brown, shining ; head light-brown ; antennae grayish, 

 brown at the base; around the ocelli black; prothorax notched behind; 

 mesothorax black, shining above ; abdomen dark brown, segments on 

 tip with a darker ring ; setse broken ; vulvar lamina long, broad, bifid, 

 the lobes elliptical ; legs thin, pale-whitish, the femora darker on tip ; 

 wings hyaline, transversal veins very fine, nearly invisible, except a few 

 on the tip of the costal margin. 



Length, 6 millimeters ; alar expansion, 15 millimeters. 



Habitat. — Nevada, Truckee in the Sierra Kevada (Crotch). 



Tarsi, 4-jointed ; the reticulation and the shape of the hind wing sim- 

 ilar to the wing of L. helvipes, figured by Mr. Eaton (Monogr., PI. iv, 26, d.). 



JHfymplia-shin (perhaps belonging to Heptagenia pudica). — Body broad, 

 flattened; head small, half as long as broad, visibly enlarged in front; 

 the hind part inflated with a rounded tubercle each side ; the front bor- 

 der cut off straight ; the sides oblique ; the front angles rounded ; the 

 w^hole border fringed with wooly hairs. Antennae short (not complete), 

 a little longer than the front border; two stronger basal joints, second 

 longer; and a conical seta, the joints of which could not be ascertained. 

 The head (for the escape of the imago) split transversely behind the 

 antennae, and the occiput in the middle; the part above the mouth- 

 parts (viewed from the front) is straight, and superseded by the de- 

 scribed flattened border, which forms a triangular projection on each 

 side; labrum transversely oblong, yellow, blackish on each side at the 

 base; mandibles and maxillae strong, yellow, with blackish apical teeth; 

 labium transversely elliptical, fourjobed, a 2 jointed large palpus 

 each side. Thorax large, nearly twice the breadth of the head, pale- 

 gray, with some brown spots; prothorax flat above, short, larger be- 

 hind, the angles sharp ; each side near the middle of the flattened bor- 

 der an exserted, conical, sharp spine; meso- and metathorax rounded 

 above, with triangular wing-cases covering the basal segments of the 

 abdomen. The wing-cases are separated by the notched hind border of 

 the metathorax; the cases of the posterior wings are not visible, and 

 seem to be connected with the anteriors in the manner of Bwtisca. 

 Abdomen a little longer than the other parts of the body, broad, flat- 



