IOWA ACADEMY OF SCIENCES 63 



Iowa, Colorado, Vancoiivers Island, British Columbia and 

 Mexico, and it has been reported from Nova Scotia and 

 Hudson Bay, by Walker. It appears to range the conti- 

 nent from Hudson Bay and British Columbia on the north 

 to at least southern Mexico on the south. 

 1? 



Ctenus Diedrocephala Spi 



Head narrower than pronotum, eyes small, vertex flat or con- 

 cave except on posterior margin, roundingly angulate, the apex 

 obtusely rounding, the margins sharp, acute, or very slightly 

 rounded and usually dark lined. Front broad, almost flat above, as 

 seen from side evenly rounding, in the same curve with clypeus. 

 Pronotum broadest across lateral angles, the side margins continu- 

 ous with the curve of anterior margin, strongly curved in front, 

 posterior margin broadly, slightly emarginate. Elytra rather long, 

 coriaceous, obscuring the venation; venation of the same pattern as 

 in Tettigonia, except that the apical cells are usually longer and 

 narrower. Anterior tibia; round or prismatic. 



This genus was founded on a South American species 

 ^ [variegafa] in which the head is very similar to that of 

 coccinea, but the apex of the elytra is slightly emarginate 

 in the middle and the outer cells very weak and obscure; 

 the venation, however, is essentially the same as in cocci- 

 nea, and the notch in the elytra, while distinct in a few 

 species, is variable or wanting in others from the same 

 region and appears to be a specific rather than a generic 

 character. 



'0 KEY TO THE SPECIES. 



A. Vertex unmarked except for a black band on the anterior 

 margin. Species robust 8 mm. or over coccinea Forst.^ 



AA. Vertex with black markings nearly parallel with the anterior 

 margin which is usually black lined, often a pair of approxi- 

 mate median lines on the disc. Smallei 6 mm, or under 



versiita Say. (^ 



Diedrocephala coccinea Forst. Plate VI, Fig. 2. 



^ Cicada coccinea Foist. Nov. Spp. Ins.. p. 96. 1781. 



Ttttigonid quadriviftata Sa.s . lour. AcaH. Nat. Sc. P'hila VI, p, 312, 1831. 

 if 'J'ef fi(/o Ilia vicf a Wa\k. Homop." Ill, p. 758, 18^1. 

 ^ y'etti(fon,iateiiro7-mis Walk. Homop. Ill, p. 764, 1851. 



Diedrocephala coccinea Osb.& Ball, Iowa .'\cad. Sc.'IV. p. 177. 1807. 

 *^ Tef.h'gonia guodrivitfafa Fnw], Bio. Homop. II. p. 276, PI. 18. Fig. 20, igoo. • 

 O TetUgonia idonea Fowl. Bio. Homop. II, p. 276, PI. 18, Fig. 22, 1900. 



Reddish with green stripes on pronotum and elytra. 

 Vertex orange, black margined. Length, 8-9 mm.; width, 

 1.75 mm. 



