Vicinity of Mason Creek, Illinois. 



301 



radius convex, its sector concave ; of the sector branches, the 

 first and the third are concave, the second convex ; the first 

 main fork of the media is convex, the second concave and their 

 branches again alternate like those of the sector ; the anterior 

 branch of the cubitus is convex, the posterior concave, the 

 twigs like those of the media ; first anal vein convex, second 

 concave. 



The spaces between all the main branches and veins are 

 traversed by cross veins, sometimes forming a diffuse net- 

 work. 



Many of the twigs or branches of the longitudinal veins have 

 the appearance of intercalary veins like those of Plectoptera 

 and Odonata, but this is only a superficial resemblance caused 

 by their strongly S-shaped curve. 



Holotype in Peabody Museum, Yale University, Cat. No. 19. 



Family uncertain. 



Amousus, new genus. 



Amousus mazonus, new species. Fig. 4. 



The basal third, 50 mm long, of probably a posterior wing. 

 There are to be seen the nearly straight costa, the moderately 

 remote subcosta and the radius, whose sector evidently rose in 



Fig. 4. 



Fig. 4. Amousus mazonus. 



the second third of the wing. The medialis splits near the 

 base, the anterior branch running for a short distance close 

 together with the radius, the posterior branch soon splitting 

 into 2 twigs. The cubitus is divided immediately after its 

 origin, its 2 forked branches running steeply to the posterior 



