the Old World Cyytacanthacrini. 141 



16 (19). Prosternal spine straight, cylindrical, 



with the apical part iuHated (tig-. 3, a). 

 Male cerci short, triangular, with the 

 apex strongly incurved. 



17 (18). Fastigium impressed, moderately sloping-, 



not closed behind; its margins scarcely 



raised. Elytra broader, with tiie apex 



neither attenuate nor bent backwards, 



(Africa: genotype, Cyrtacanthacris [nov. 



dehilis, Karsch.) 7. Bryophijma, gen. 



18 (17). Fastigium impressed, strongly sloping, 



closed (or almost so) behind ; its mar- 

 gins distinctly raised, continent with 

 the margins of the frontal ridge. 

 Elytra narrower, with the apex at- 

 tenuate and bent backwards (fig. 6, b). 



(Africa : genotype, Cyrtacimthacris [nov. 



tectifenis, Karsch.) 8. Rhytidacris, gen. 



19 (16). Prosternal spine either not cylindrical or 



with the apex not inflated. 

 20(27). Fastigium impressed, forming (when 

 viewed in profile) a distinct, though 

 rounded, angle with the frontal ridge ; 

 the latter well developed throughout, 

 with the margins callous (fig. 3, h). 



21 (26). Hind femora and tibiae normally built. 



22 (23). Elytra broad, apically scarcely narrowed 



and obliquely truncate. Male cerci 

 strongly laterally compressed, parallel- 

 sided, shorter than the anal plate, with 

 the apex broad, subemarginate ; male 

 subgenital plate with the apex divided 

 into two triangular lobes. (Africa, 

 Asia, S. ilmerica : genotype, Gryllns 

 gregarius, Forsk.) 9. Schistocerca, St. 



23 (22). Elytra very nrn-ow (fig. 5, c) or with the 



apex attenuate (fig. 6, c). 



24 (25). Face distinctly reclinate. Elytra very 



narrow, parallel-sided (fig. 5, c). Male 

 cerci short, strongly laterally com- 

 pressed, triangular; male subgenital 

 plate conical. Wings hyaline. (Ma- 

 dagascar: ^QTiotj^e, Acridiumschisto- [gen. nov, 

 cercoides, Brancs.) 10. Rhadinacris, 



25 (24). Face vertical or practically so. Elytra 



not very narrow, but with the apex at- 

 tenuate and bent backwards (fig. 6, c). 

 Male cerci round, narrow, at least as 

 long as the anal plate, curved ; male 

 subgenital plate with the apex tri- 

 lobate. Wings with the base or a 

 submedian fascia infumate. (Africa, 



S. Europe, Asia : genotype, Gryllus [gen. nov 



Locusta cegyptia, L.) . . . .' 11. AnacridiuDi, 



26 (21). Hind femora extremely narrow ; hind 



tibiae strongly laterally compressed at 



