1918.] NATURAL SCIENCES OF PHILADELPHIA. 149 



Ischnoptera oastanea Saussure. (Pi. I, figs. 13, 14.) 



1869. I[schnopterd\ castanea Saussure, Revue et Maga.sin de Zoologie, 2e 

 ser., XXI, p. 112. [Brazil.] 



Igarape-assu. One male. 



This specimen fully agrees with the original description, as far as it 

 supplies characters derived from the female sex. As the male genital 

 characters have never been described, the following notes on the same 

 should prove of assistance. 



Supra-anal plate moderately transverse, the margin broadly arcu- 

 ate, appreciably flattened in the middle and there very weakly bilo- 

 bate, cereal emargination decided, regularly concave, margin between 

 apex and cereal emargination moderately arcuate; surface of plate 

 sub-depressed proximo-laterad, with a distinct, broad, median im- 

 pression on distal half: distal portion of margin very sparsely haired: 

 ventral surface of supra-anal plate with patches of short, agglutinated 

 hairs on the faint lobes of the distal margin, also meso-laterad on the 

 body of the plate, while a distinct, tuberculiform node is situated 

 immediately mesad of the dextral cercus; immediately mesad of the 

 sinistral cercus there projects ventrad a heavy, claw-like process, 

 which is nearly straight and robust in the proximal two-thirds, thence 

 sharply bent mesad and straight acuminate: from immediately ven- 

 trad of the dextral cercus springs an unpaired lamellate, articulate 

 process, a portion of the internal genitalia, the dorsal surface of the 

 same bearing in proximal two-thirds a carinate ridge, the apical sec- 

 tion rotated dorsad and weakly rostrate, bearing five distmct teeth: 

 genital hook slender, bent recurved, the apex slightlj'^ flattened. Sub- 

 genital plate faintly asymmetrical, with dextral, sinistral and median 

 emarginations, between which are short, truncate projections of the 

 margin of the plate; sinistral emargination broad, faintly angled 

 mesad; median emargination regular; dextral emargination small 

 but deep and rectangulate; styles unequal in size and development, 

 the sinistral large, straight proximad, acuminate distad, distal half 

 decurved; dextral style smaller, regularly acuminate, decurved; 

 margin of the plate and styles sparsely haired; dorsal surface of the 

 subgenital plate at base of dextral style with an erect, laterad directed, 

 lamellate lobe, bearing at the internal angle of the apex a distinct, 

 dentiform spine. 



Ischnoptera imparata n. .sp. (Pi. I, figs. 5-8.) 



This peculiar species appears to be allied on one hand to I. castanea 

 Saussure, and on the other to I. amazonica Rehn,^ but it can be recog- 



8 Trans. Amer. Entom. Soc, XLII, p. 225, (1916). 



