REVISION OF ELEODITNI BLAISDELL. 



39 



the former; antennal modification resulted in racial divergence in 

 quadricoUis^ while greater calcarine development characterized the 

 liunieralts ramus. 



In the Carhonar'ta section crural development seems to have taken 

 place, not atl'ecting the main cafhonana stem where surface sculptur- 

 ing has undergone modification along two lines, the smooth and the 

 asperate as indicated in the synopsis of the species. 



Group I appears to be very plastic and reactive to modifying 

 forces; (Iroup II less so. In Group I there is evidence of greater 

 specific and racial differentiations. 



Porcafa 



Carionaria 



CuneaticolUs 

 Humeral is 



Pedinoides 



Neomexicaiia 



"Wcostata 



Subgeneric IVuTik; 



Pif!. 1. — Genealogical diagram of the subgexi's melanelodes. 



The species of the present subgenus may be divided into two groups 

 as follows: 



Elytra elongate oval, convex, comparatively narrow, feebly emarginate at base, 

 humeral angles not rectangular; thorax not conspicuously broadened at base, 

 angles obtuse, not overlapping humeral angles of elytra, more or less arcuately 

 declivous at the sides, marginal bead rarely entirely visible when viewed 

 vertically from above Group I. 



Elytra broad, flattened, truncate at base, humeral angles rectangular ; thorax 

 conspicuously broadened at l)ase, angles rectangular, overlapping the humeral 

 angles of the elytra ; pronotum but slightly arcuately declivous at the sides, 

 marginal bead distinctly visible from above Group II. 



Group I may again be conveniently divided into two sections: 



Anterior spur of anterior tibire more or less gradually narrowed from base to 

 apex in both sexes Carbonaria Section. 



Anterior spur of anterior tibia^ more or less decidedly thicliened in both sexes ; 

 gradually narrowing from base to ai)ex in the male; much thickened and sub- 

 parallel, narrowed more or less gradually beyond the middle third or basal 

 half, subacute or obtusely rounded when worn QtuidricoJUs Section. 



