169 



abdomen not inflated ; sub-genital plate somewhat elongate; cerci flat. Sul)- 

 genital plate of the female has a tringular tooth at the middle of the apex. 

 Legs rather robust; posterior long, the femora reaching to or passing the 

 apex of the abdomen. Prosternal spine stout, prominent, straight or curved 

 backward. 



Synoptical table of the species. 



A. Elytra longer than the abdomen : 



a. Elytra with spots : 



h. General color bright reddish browQ ; wings with dark nerves. .. americanum. 



hh. General color light yellowish-brown : 



c. Spots on the elytra large and distinct amhigiium. 



cc. Spots on the elytra small and indistinct alutaceum. 



aa. Elytra without spots: 



J). General color green : 



c. A yellow strii^e along the dorsum ohscurmn. 



CO. Without any stripe along the dorsum shoshone. 



hh. General color yellowish-brown ; a yellow dorsal strij)e emarginatum. 



AA. Elytra about as long as the abdomen : 



a. Uniform light rust-red ; dim spots sometimes visible on the 



elytra, generally without them rubiginosum. 



aa. Small size; elytra greenish, unspotted: 



b. Piceous patches on the sides of the prouotum ; wings cinereous . . unilineata. 

 bb. Sides of the prouotum green with glabrous spots ; wings 



transparent frontalis. 



A. fromSalis, Thos., Hayden's Geol. Surv. Terr., 1871, 448, PI. ii, Fig. 1. 



Vertex sub-conical. Small size. Elytra and wings not passing the 

 abdomen. General color green. 



Closely allied to A. unilineatmn, "Walk. ; caloptenoid in general appear- 

 ance. Vertex regularly hexagonal, standing out in the form of a very short, 

 truncated cone, the tip depressed in the center ; face slightly oblique, straight, 

 quadricarinate ; carinas nearly parallel, middle pair approach each other im- 

 mediately below the ocellus. Eyes elongate, oblique, straight in front. Pro- 

 notum scarcely enlarged behind ; anterior lobes reticulately, and posterior 

 lobe longitudinally, rugulose ; median carina very distinct. Elytra and wings 

 narrow, rather shorter than the abdomen. Valves of the ovipositor promi- 

 nent, lower pair much slenderer than the upper pair, and much exserted. 

 Male cerci slender, tapering, and turned up ; sub-anal plate narrow, tapering, 

 sub-truncate at the apex, entire. Prosternal spine sub-quadrate, pointed, and 

 22 A 



