June, 1913.] AldRICH : NORTH AMERICAN SPECIES OF LiSPA. 140 



the rest shining ; fourth segment with a still larger white pruinose spot on 

 each side against the front border, the rest shining; fifth segment wholly- 

 shining black, but little visible. Venter grayish white. Bristles of abdomen 

 not of noticeable size except on the fourth and fifth segments. 



Legs and pleurae covered with plumbeous pruinosity ; knees yellow; front 

 tarsi of very characteristic structure, longer than their tibiae, the first joint 

 short, usually yellow, with a tuft of black bristles below, and prolonged in a 

 yellow process along the side of the second joint, the process one half longer 

 than the first joint itself, and with a black tip; second joint yellow, about 

 half as long as the tibia; remaining joints becoming darker, longer than in 

 most species. Middle femora rather slender and blackish toward the apex, 

 with only short hairs and bristles, their tibiae with a single bristle on the outer 

 side at the middle, their tarsi slender and long, a little pale at base ; hind 

 femora with long, slender bristles or hairs below in a sparse row beginning 

 before the middle, the tibiae with about three irregularly spaced bristles on 

 the hind side and soft, long hair on the inner side; hind tibia 1.03 times the 

 tarsus, first joint of the latter with a brush of hair below, not much over half 

 as long as the four following. Length 5.5 mm. 



Female. — Head 2.35 times the front in width ; front tarsus black, the first 

 joint of ordinary form, nearly twice as long as the second, the whole tarsus 

 about I Yi times the length of the tibia, hind tarsus a little longer than its 

 tibia; the hind femur generally has a single long, hairlike bristle on the under 

 side beyond the middle (occasionally two). Palpi not quite so shining, but 

 nearly as large as in the J'. Length 7 mm. 



This is the most abundant species ; Becker reports it everywhere 

 common in Europe around fresh water, also from the Canary Islands 

 and Central Asia. I have it in abundance from South Dakota, Kan- 

 sas, Idaho, Utah, Nevada, Oregon and Washington, and it has been 

 recorded from New England and California. It is seldom sought 

 in vain at the edge of fresh water during the entire collecting season, 

 in my experience. 



Sociabilis and patcUata are very closely related to this species ; the 

 differences I have summarized under their respective descriptions. 



Lispa patellata new species. 



]\Iale. — Head 2.70 times the width of front, the latter widening very 

 slightly above, blackish including the middle and upper parts of the orbits ; 

 the last with fine hairs which continue uniformly down the sides of the face ; 

 entire face including sides brown pollinose, no band across root of antennae ; 

 antennae black, second joint at tip with a white pollinose roundish spot when 

 viewed diagonally from below ; arista rather thin pilose ; vibrissae large, with 

 smaller bristbes extending back under the head; palpi of immense size, glisten- 

 ing white, slightly flesh-colored, as wide as the full length of the antenna and 

 the enlarged part nearly a half longer, suddenly widened downward from the 



