130 Mr. B. P. Uvarov— .1 Revision of 



XT. — A Bevision of the Old World Cyrtacanthacrini 

 {Orthoptera, Acrididse). — I.^ Introduction and Key to 

 Genera. By B. P. Uvarov, F.E.S., Assistant Ento- 

 mologist, Imperial Bureau of Entomology. 



The group Cyrtacanthacrini comprises mostly large, or 

 middle-sized, grasshoppers, characterised by the presence of 

 a well-developed prosternal spine, by the lack of the outer 

 apical spine of the hind tibise, and, more particularly, by the 

 inner angles of the mesosternal lobes being straight or acute, 

 but not rounded, and their inner margins rectangular or 

 concave, but never convex (see figs. 1 A, B, C). Practically 

 all authors have considered this peculiar shape of the meso- 

 sternal lobes as a generic character, and all the species 

 possessing it, no matter how nnlike each other they may be 



Fig-.]. 



Sternum : A, Aeridoderes crassus, Bol. ; B, Valanga nigricornis (Burm.) ; 

 C, Patanya suecincta (L.)* ^ ^' 



in other characters, have been treated as congeneric and 

 identified as Acridium spp., according to Serville's vague 

 definition of the genus. Asa consequence, more than one 

 hundred species have been described under Acridium^ many 

 of them strikingly dissimilar and obviously not congeneric. 

 This made the identification of species very difficult and 

 nncertain, and as the majority of species, owing to their 

 large size, have already been described long ago by older 

 authors, who paid little attention to morphological characters 

 and founded their species almost solely on coloration, the 

 confusion of species has become quite overwhelming and a 

 thorough revision is indispensable, the more so that the 

 group includes also some of the most important swarming 



