224 DAVENPORT ACADEMY OF NATURAL SCIENCES. 



rounded outline of the humeral angles. The median carina is distinct 

 and accompanied by more or less distinct supijlementary carinse on the 

 disk. All of these are cut by the last princij^al sulcus only, a little or 

 considerably l)ehind the middle. The posterior angle of the disk is 

 moderately rounded. The lateral lobes of the pronotum are a little 

 higher than long with the anterior margin strongly oblicpie, the poste- 

 ^rior margin perpendicular and the lower margin slightly angulate. 

 The mesosternal lobes are separated by a space broader than (female) 

 or as broad as long (male), and the metasternal lobes by a space longer 

 than broad (female) or very nearly approximate (male). The tegmina 

 are well developed, with the scapular area of the male exjianded, hya- 

 line and filled with rather prominent cross veins. The discoidal area 

 has no intercalary vein, and the dividing is soon united with the pli- 

 cate vein. The posterior femora are banded with fuscus on the upper 

 and inner faces. The uj)per valves of the ovipositor are included, the 

 lower valves slightly exerted. The posterior tibiiie are bluish, with the 

 apical inner spur sub-equal to the one behind it, much less than twice 

 as long. 



This genus includes two western species, it is closely related to the 

 following genus and less intimately to Eritettix. From the last-men- 

 tioned genus it is easily distinguished by the absence of lateral carinae 

 ujjon the top of the head, and the median carina except at the vertex, 

 by the absence of the club to the antennje, by the rounded disk of the 

 pronotum and the obsolete lateral carinse, by the banded hind femora, 

 the blue hind tibiae with sul)-e(iual inner apical spurs, and by the un- 

 spotted tegmina. 



Key to amphitornus, n. gen. 



A.' Median carina cut very little l)ehind the middle ; 



I . — Bicolo), Thos. 



A. 2 Median carina cut decidedly behind the middle. 2. — Ornatus, n.sp. 



I. Amphitornus BicoLOR, Thos. Fig. iia, iib. 



Stenolwf/irus />i(-o/or,T\\o?,. , 1872. Prelim. Rept. U.S. Geol. Surv. 

 Mont., 465. 



Stenobothriis bicolor, var. a., Thos., 1872. Prelim. Rept. U. S. 

 Geol. Surv. Mont., 465. 



Stenobothriis coloradiis, Thos., 1873. Syn. Acrid. N. A., 82. 



Stenobothriis coloradiis wiicolor. Thos. , 1873. Syn. Acrid. N. Am. , 83. 



Stenobothriis coloradiis, T\\o^. , 1876. Proc. Dav. Acad. Nat. Sci., 

 I, 251. 



