112 STUDIES IN NORTH AMERICAN MEMURACID/E 



horn is always much shorter than in the female. Say redes - 

 cribed it as Membracis latipes and Walker has added at least 

 five other synonyms. 



Genus Enchenopa A. & S. 



Dark ferruginous brown or piceous black ; anterior process long 

 and curved forward at apex; dorsal carina prominent 

 posteriorly, whitish, usually interrupted behind the 

 middle; inhabits eastern United States, 



i, binotata Say. 



Pale yellowish or testaceous yellow ; anterior process straight, 

 moderately elevated ; dorsal carina not elevated poster- 

 iorly, bisinuate, pale with a dark median spot and tip; 

 inhabits western states, 2, permutata V. D. 



Enchenopa binotata Say. 



Common and widely distributed in the United States and 

 Canada. It varies much in the form of the pronotal horn but I 

 cannot discover any characters that seem to be of specific value. 

 Enchenopa porrccta Buckton and hrevis Walker are doubtless 

 synonyms of this species. 



Enchenopa permutata n. sp. 



Pale testaceous varied with darker on the sides and along 

 the pronotal horn and marked with fuscous, sometimes obscure- 

 ly, behind the middle of the dorsum and at the extreme tip of 

 the pronotum ; sternum and venter brown. 



Pronotum anteriorly produced in an oblique compressed 

 process obviously longer than wide at base, its apex narrower 

 and obtusely rounded. Dorsum distinctly sinuated before the 

 acute apex before which it is feebly arcuated on the fuscous 

 dorsal spot. Lateral carinae but little elevated on the sides of 

 the anterior process, attaining the lateral margin at about its 

 middle. Median carina of the metopidium becoming more 

 broadly elevated or almost foliaceous on the anterior process 

 where it is more prominent than in binotata. Length to tip of 

 the pronotal horn 5 mm. 



Described from 10 females taken by Prof. Wickham at St. 

 George, Utah, in July, and two other females from Arizona in 



