112 NEW YORK STATE MUSEUM 



Eniscopilus arcuatus Felt 



This comparatively rare species may be easily separated from 

 E. p u r g a t u s Say, with which it has heretofore been confused, 

 by the well marked chitinous, usually yellowish, arcuate con- 

 tinuation of the larger opaque spot in the cubitodiscoidal cell. 

 This structure extends along the posterior border of the glabrous 

 area in that cell to a point beyond the smaller opaque spot. It 

 may also be recognized by the bulla of the cubitodiscoidal cell 

 being at a distance equal to one half the width of the third dis- 

 coidal cell from the apex of the same [pi. 1]. 



This species was described in the February issue of Psyche, 

 1902, page 307-8, and its characterization is reproduced herewith : 



Light fulvo-ferruginous, the larger opaque chitinous spot of the 

 cubitodiscoidal cell with a distinct arcuate continuation extend- 

 ing along the hinder margin of the glabrous area and partly 

 around the smaller chitinous spot. 



Head medium, yellowish posteriorly, face yellowish, antennae 

 slightly longer than the body; ocelli black, equidistant; mandi- 

 bles bidentate, fuscus apically. Thorax, sericeous ; mesothorax, 

 convex; scutellum and postscutellum, prominent, the former yel- 

 lowish; meta thorax slightly depressed in front of the transverse 

 carina; lateral carinae distinct. Wings hyaline, having hardly a 

 trace of the fuscus visible in Ophion (Eniscopilus) 

 purgatu-s Say; marginal nervure slightly thickened and sin- 

 uate near the small stigma ; cubitodiscoidal nervure, weakly 

 sinuate, not appendiculate; its bulla one half the width of the 

 third discoidal cell from its apex; two subtriangular opaque spots 

 in the glabrous area of the cubitodiscoidal cell, the larger one 

 with a chitinous, usually yellowish continuation along the hinder 

 margin of the glabrous area to a point beyond the smaller 

 chitinous spot, which latter is anterior and lateral of the center 

 of the glabrous area. Legs, honey yellow. Abdomen, strongly 

 compressed, slightly darker at the tip, the first and second seg- 

 ments being very slender. The claspers of the male are rounded 

 apically. 



Length about 23 mm. Wing spread from 30 to 35 mm. 



Habitat, Albany N. Y. May 0, 1876 [W. M. Hill] : Ithaca N. Y., 

 July 16, 1889 [J. M. Stedman] ; New York city [L. H. Joutel] ; 

 Maiden Mass. [C. H. Fernald] ; Poughkeepsie N. Y. [Young, col- 

 lector] ; South Britain Ct. 1S84 [G. F. Fierce]. 



