MCNEILL REVISION OF THE TRUXALIN^ OF NORTH AMERICA. 253 



I. Plectrophorus viATORius, Sauss. Figs. 2ia, 2ib, 2IC. 



Stenobothriis viatorius, Sauss., 1861. Orth. Nov. Am., II, 20. 

 Stenobofhrus viatorius, Thos., 1873. Syn. Acrid. N. Am., 206. 

 Scylliiia viatoria, Stal, 1873. Recen. Orth., I, 112. 

 Hab. All of Mexico, where it is common and injurious (Sauss.). 

 I have specimens from Orizaba and Tlalpam. 



2. Plectrophorus gregarius, Sauss. 



Sienobothnis ^regarius, Sauss., 1861. Orth. Nov. Am., II, 20. 

 Stenobothriis gregarius, Thos., 1873. Syn. Acrid. N. Am., 206. 

 Hab. Islands of St. Thomas and Hayti (Sauss.). 

 I am unacquainted with the species, but it probably belongs to this 

 genus. 



XXll. MECOSTETHUS, Fieb. Fig. 22. 



Vertex horizontally produced with a median carina more or less dis- 

 tinct and with lateral carina distinct, straight, meeting in a sharp or 

 rounded point in front to form an angle a little greater or a little less 

 than 90 degrees. The lateral foveolje are very small, triangular, basal 

 (distant from the vertex) visible from above, sometimes almost obso- 

 lete. The frontal costa is continued distinctly almost to the clypeus, 

 it is sulcate at least below the ocellus. The antennce are filiform, much 

 longer (male) or about as long (female) as the head and i)ronotum to- 

 gether. The pronotum is plain above with all the carinae distinct, the 

 median cut in or a little in advance of the middle, the lateral cut by 

 the principal sulcus only or by either or both of the other sulci as well. 

 The metazone is very obtusely angled. The lateral lobes of the pro- 

 notum are at least as high as long with the anterior and posterior mar- 

 gins sub- perpendicular, and with the lower margins only moderately 

 obtuse and but little rounded at the apex. The tegmina are well de- 

 veloped in both sexes, the mediastine vein is well developed, extend- 

 ing beyond the middle and the costal field is expanded at the 

 base and furnished with an adventitious vein. The scapular area is 

 but little expanded in the male and is about equal in both sexes. The 

 discoidal area is furnished with a very prominent intercalary vein 

 which is nearer the ulnar than the radial vein. This area is occupied 

 by a double series of strong cross-veins and forms the musical organ 

 in the male. The posterior femora are somewhat longer than usual, 

 extending beyond the end of the abdomen in the male. The last 



[Proo. D. a. N. S., VoL VI.] 32 [January 5, 1897.] 



