14 BRITISH CICADA. 



AcocEPHALUs NERVosus, Schvank. Plate XLI., figs. 

 4 to 4 a, and Plate XLII., figs. 2 and 3. 



Cicada nervosa, Schrank. 



Acocephalus cavdui, ohscurus, sparsiis, unicolor, fasciatus, 



pallidiis and bicinctus of Curtis ; adushis of Hardy. 

 Acocephalus rusticus, Flor ; Marsh. ; Kirschb. ; Sahib. ; 



Sign., Ess. Jass. pi. i. fig. 6, p. 62 ; Edw. pt. ii. 



p. 19. 



This large and common species has an extensive 

 synonymy, only a part of which is to be found in the 

 above list. 



The variations in size are as remarkable as those of 

 colom'. Some specimens are almost miiformly ochreoiis 

 in colour, whilst others are dark brown or nearly black. 

 Some are yellow, with a single fine band of umber- 

 brown across the bases of the elytra, whilst others 

 have the head and pronotum ochreous, and the elytra 

 profusely spotted and mottled with black, grey patches 

 appearing on the corium and the costal edges. A 

 rather common variety is of a ferruginous -brown, with 

 black eyes and mottled elytra. 



The varying flatness of the vertex, with its deep 

 depressions and marked frontal carina, is observable ; 

 as also is the more or less produced acute form of the 

 head itself. 



Male. Head roughly punctured. Vertical carina 

 usually very marked. Pronotum rugose and a little 

 longer than the head. Scutellum rather small. Elytra 

 rough ; nervures pale and raised. Abdomen black. 

 Genital plates yellow, long, straight, and obtusely 

 pointed. The groove deep. Hypopygium longer than 

 broad (sometimes shorter), pubescent. The anal style 

 or Cauda scarcely visible. 



Female. Greenish or dirty yellow ; usually speckled 

 with brown or with paler spots. 



