1886.] NATURAL 80IEN0E8 OP PHILADELPHIA. 15 



luteous. Abdomen pale brown, the sutures and underneath in 

 part pale. Legs pale, femora somewhat yellowish. Wings per- 

 fectly hyaline, the veins pale brown, semitransparent luteous in 

 parts ; pterostigma, a narrow space directly beneath it, and the 

 indication of a small spot at the junction of the cubitus and pos- 

 terior margin, pale brown. Length to end of wing about 2'5 mill. 

 Southern Texas. One specimen taken from the live oak trees 

 that compose the small groves (motts) on the prairies. It is 

 allied to Ps. quietus, of Hagen (many specimens of which I also 

 found in the same locality, but in different situations, viz. : on 

 yellow berry bushes), but differs from that species in being con- 

 siderably smaller, in having the nasus shorter, not reaching the 

 ocelli, and by having fewer markings on the head. 



Psocus Leidyi. Plate I, fig. 2. 



Pale yellowish and black. Antennae nearly as long as the 

 wings, subfuscous, the basal joints pale ; palpi pale, the apical 

 joint subfuscous. Head pale yellowish, deepest <Sn the nasus, 

 which is faintly lineated with paler ; a large shining black 

 rounded spot in the middle of the upper part of the nasus, bor- 

 dering the suture ; beneath the antennae, on each side, a small 

 black spot ; ocelli black ; occiput with a brown band on the 

 dividing suture containing a double row of darker spots almost 

 reaching the ocelli. Eyes black. Lobes of the thorax black, 

 shining, the sutures and the rest of the thorax pale yellow. 

 Abdomen pale yellow, the sutures black, merging into a longitu- 

 dinal row of irregular spots on each side of the dorsum ; a large, 

 irregular, shining black patch on the dorsum of the apical seg- 

 ment, with a smaller black spot on each side below it. Abdo- 

 men beneath partly fuscous. Apical appendages, yellow and 

 black. Legs very pale, the base of the tibia with a black spot 

 beneath, and the tarsi subfuscous, the apical joint black. Wings 

 clear hyaline, veins mostly fuscous, that enclosing the pteros- 

 tigma yellow, and the veins enclosing the discoidal cellule, with 

 certain of their branches, in part pale yellowish and light brown. 

 Pterostigma subopaque, a small black spot at its base, a rounded 

 clouded brown spot posteriorly within its apex, and another 

 brown spot directly below and contiguous to its posterior angle ; 

 at the basal angle of the discoidal cell a large rounded brown 

 spot, and another smaller at the junction of the cubitus and 



