74 PROCEEDINGS OF THE ACADEMY OF [March, 



looking quite different from the short, rounded sub-rectangulate 

 extreme found in the Baboquivari Mountains individuals, and 

 relatively closely approximated in a number of the specimens 

 from other localities. 



The angle of declivence of the facial line shows considerable 

 variation, being, as a rule, more strongly retreating in the more 

 slender individuals. Thus the least retreating faces are found 

 in the more robust Babocjuivari specimens, but there is very con- 

 siderable variation in that series in this respect, so much so that 

 extremes from that locality have their heads, when viewed from 

 the side, quite different in general inclination of the face. The 

 frontal costa varies, of course, in its width and also in its relative 

 depth, with the greater or lesser narrowing of the general form, 

 the quite slender specimens having the costa narrow and with 

 the sulcus more regularly defined, deeper and, as would be ex- 

 pected, narrower and more sharply defined dorsad than in the 

 more robust specimens. 



The tegmina show a slight amount of variation in their relative 

 width, but this is not at all decided. See Remarks for discussion 

 of the value of the morphological differences. 



Synonymy. — Stal's helfragii is clearly the same as Thomas' 

 older species. The description is matched by numerous indi- 

 viduals in the series before us. The name was first properly 

 synonymized by McNeill in 1897. 



Measurements {in millimeters) . 



<f Length of Length of 



body. pronotum. 



Hot Springs, South Dakota 29 4.4 



Little Big Horn River, Montana 28.5 4.6 



Havana, Ilhnois 32.2 4.6 



Sidney, Nebraska / 26.4 4.1 



Sidney, Nebraska 27 4.4 



Dodge City, Kansas 28.5 4.6 



Dodge City, Kansas 3L2 4.8 



Syracuse, Kansas 33.8 5.2 



Syracuse, Kansas. .■ 34 5.1 



Julesburg, Colorado 29.5 4.8 



Holly, Colorado 37,1 5.5 



La Junta, Colorado 29.7 5 



La Junta, Colorado 31 5 



Cache, Oklahoma 35.3 5 



Mountain Park, Oklahoma 36.6 5.1 



Summit of Mt. Sheridan, Oklahoma. 35 5.3 



Dallas, Texas 32 4.7 



Dallas, Texas 36.5 5.6 



