IIO STUDIES IN NORTH AMERICAN MEMBRACIU/E 



ical News which are probably new if not forms of one species. 

 They are still unknown to me. He described P. minax from 

 a horned specimen and P. asodalis from an unarmed form. 



Subfamily Membracida Stal. 



KEY TO THE GENERA: 



Head short, the base transverse and tumid, the small triangular 

 apex much depressed; pronotum elongated, depressed, 

 bisinuate behind; size small, 9, Centrodontus Godg. 



Head flat or nearly so, the apical portion not abruptly depressed 

 below the level of the base, 1. 



1. Head distinctly trilobate at apex, the broad rounded cly- 



peus produced for at least half its length before the line 

 of the cheeks; pronotum elevated anteriorly in a slightly 

 inclined angular process which is bifed at apex by the 

 incised median carina; size small, 6, Midtarcis Godg. 

 -. Head long and rounded or truncated at apex; porrect pro- 

 cess if any not bifed at apex, 2. 



2. Pronotum much elevated, thin and foliaceous, the dorsal 



outline regularly rounded before, 1, Membracis Fabr. 



Pronotum more or less elevated or obtusely rounded above, 



sometimes moderately foliaceous but in that case angled 



or produced in a crest anteriorly, 3. 



3. Form oblong or elongated; pronotum more or less com- 



pressed laterally and furnished with a distinct dorsal 

 carina, 4. 



-. Form short or even subglobose, not at all compressed and 

 without a distinct dorsal carina; surface roughly corru- 

 gated, 8, Bolbonota A. & S. 



4. Pronotum with a long oblique anterior process, the poste- 



rior process little elevated, attaining the apex of the 



elytra, 10, Pliilya Walk. 



-. Posterior process of the pronotum not attaining the apex 



of the elytra, 5. 



5. Pronotum distinctly compressed elevated, produced anter- 



iorly in a prominent, usually oblique, compressed process, 



6. 



