Vicinity of Mason Creek, Illinois. 



377 



The greatest breadth situated below the middle. Costa 

 marginal. Subcosta produced somewhat beyond the middle 

 and united with the radius, these two veins very near the 

 anterior margin. Sector rising at about one-third of the 

 length, moderately diverging from the radius and giving off 2 

 branches. The media sends a branch in the form of an 



Fig. 02. 



•*,» 



M 



Fig. 62. Prochoroptera calopteryx (fore wing), x 3. 

 Fig. 63. 



Fig. 63. Prochoroptera calopteryx (hind wing). x 3. 



oblique cross vein to the sector, continuing its course as a 

 branch of the latter. The stem of the media soon forks again 

 and these forked branches are broken on the points of inser- 

 tion of the cross veins. First cubital branch simple, free ; 

 the second split into 3 twigs. Anal vein of the anterior wing 

 forming a regular vault and giving rise to 3 oblique branches, 

 directed backward. In the posterior wing the anal vein is 

 broken and has also 3 branches. The whole medio-eubital 

 and anal area, by the breaking of the veins at the insertion of 

 the cross veins, chiefly in the hind wing, has a very singular 

 aspect which recalls some JSTeuroptera, for example, Raphidia. 

 The small number of regularly arranged cross veins, the shape 

 of the homonomous wings, the fusion of the sector with the 

 media, seem to indicate a close relationship with the Megase- 

 coptera. 



The length of .the whole insect is 29 mm , that of the 

 anterior wing about 32 mm , and of the posterior wing 28 mm . 



Holotype in Peabody Museum, Yale University, Cat. No. 67. 



