June, ]qi3.] AlDRICH : XORTH AMERICAN SpECIES OF LiSPA. 127 



The genus Lispa is one of these easily recognized ones. It belongs 

 to the second section of the family, having the front broad in the male 

 as well as in the female, and in this section differing from all its 

 congeners in having in both sexes great dilated palpi, generally some- 

 what spoon-shaped, and either black or yellow in color. The species 

 are found at the edge of water, and occur in abundance throughout 

 the season everywhere in the United States ; two or three species can 

 be found in any neighborhood. Nothing definite is known about the 

 larval habits, but by elimination it would appear that they must occur 

 in the mud in the immediate vicinity of the adults. The commonest 

 species are about the size, shape and color of a house-fly. 



The known North American species agree closely in most of their 

 characters, which are given below at some length to avoid repetition 

 in the specific descriptions. 



Generic Characters. — Front broad in both sexes, with a row of 

 about 6 orbital bristles, the upper two curving backward or nearly 

 erect, the rest curving toward the middle line ; orbits hairy between the 

 eye and these bristles; no hairs or bristles on the front between the 

 ocelli and the antennse ; a large pair of ocellar bristles and numerous 

 hairs between and behind the ocelli. Antennae not very long, arista 

 thickened at base, plumose. Face concave, epistoma projecting, with 

 large vibrissae and some smaller bristles, which continue back along the 

 sides of the mouth cavity (in palposa the males and some females 

 WMthout vibrissae, or these indistinguishable from the other bristles) ; 

 facial orbits with small hairs, which in some species are continuous 

 with those of the frontal orbits; head somewhat protuberant at the 

 insertion of the antennae, often with a contrasting black velvety 

 transverse band turned up at the ends, across the base of the antennae. 

 Palpi greatly dilated at tip, either suddenly or gradually, more or less 

 bare and glistening on the expanded portion. Proboscis short, small, 

 horny, labella of medium size. Back of head protuberant, hairy; 

 vertical bristles 2 pairs as usual; one pair of small post-verticals, 

 occiput bare. 



Thorax somewhat narrow and elongate, with the following chseto- 

 taxy : dorsocentrals 5, 3 behind the suture (itasoni has 6, 4 behind 

 the suture): acrostichal merely hairs; notopleural 2; presutural i; 

 posthumeral (intrahumeral) i ; humeral 2 or more; supra-alar i ; intra- 

 alar 2; posta!ar 2; scutellar 2 (pairs); prothoracic (above the front 



