June, 1913] AlDRICII : NORTII AMERICAN SpECIES OF LiSPA. 133 



spot each side on the posterior half; on the third the same parts are more 

 shining; the posterior half of the fourth is shining, but narrowed at the sides; 

 the third segment has appressed marginal macrochsetse, the fourth has about 

 4 discal and 8 marginal ones, not appressed; the posterior edge of the fourth 

 sternite stands out from the body, is very hairy, and has a notch in the middle, 

 as well as several bristles ; fifth tergite moderately prominent, hairy and 

 bristly, velvet-black, with a chalk-white median dorsal spot extending the 

 whole length and about one-third the width. Organs of the hypopygium 

 closely folded in, not distinguishable. 



Legs entirely black, knees not appreciably lighter ; front legs plain, the 

 tarsal joints of regularly decreasing length ; middle femora rather long, a 

 little attenuated at tip, with two or three excessively long hair-like bristles on 

 the front side at base and a few shorter, but still long ones on the under side 

 at base; middle tibiae long, with one bristle on the front outer side and two on 

 the hind outer side, before the preapical ; middle tarsus with a shortened 

 second joint, which in specimens is generally bent at an angle with the first 

 and third, — it is of normal structure, shorter than the third and about the 

 same length as the fourth ; hind femora rather slender, the under bristles 

 strong, hind tibiae with two small bristles near the middle ; hind tarsi short, 

 their tibiae 1.39 times their length, first joint as long as all the others, which 

 taper off and end in unusually small claws and no pulvilli. 



Wings faintly brownish, veins brown. Length 6 mm. ; of wing 5 mm. 



Female. — Front wider than in the male, the head 2.42 times its width ; 

 tarsi of plain structure, hind ones barely shorter than their tibiae ; abdomen 

 generally less shining, sometimes with median blackish stripe, fifth segment 

 with 6 or 8 discal macrochaetae, fifth and sixth segments retracted, but with a 

 trace of white mark above. Length 8 mm. ; of wing 6 mm. 



Numerous specimens of both sexes, collected at the edges of saline 



water (Box Elder Lake), Brigham City, Utah, July 4 and 5, 191 1. 



Lispa palposa Walker. 



Male. — Front nearly black (the head 2.62 times the front in width), upper 

 part of the ocellar triangle brown, orbital margins narrowly yellowish, with a 

 single row of hairs next to the eye; a very striking velvety black band from 

 eye to eye at the level of the insertion of the antennae and below ; antennae 

 black, the first two joints velvety, arista long-plumose; sides of face with a 

 clear silvery sheen, bare except low down ; middle of face concolorous ; 

 vibrissae hardly distinguishable from the small bristles of the sides of the 

 mouth ; palpi velvety black, suddenly enlarged about the middle, with long 

 black hairs on the front and lower edge ; proboscis black, of ordinary form ; 

 the usual erect small bristles of the back of the head arranged somewhat 

 in rows. 



Thorax black in ground color, gray pruinose, with the beginnings of four 

 black stripes in front, the median two more distinct and extending farther 

 back ; chaetotaxy normal ; calypteres ivory-white with brown border ; halteres 

 yellow with brown knob. 



