MORGAN HEBARD 215 



This species averages smallest of the genus, the largest of 

 the twenty-eight males in the Philadelphia Collections being 

 no larger than the smallest of the eighteen males of apacha at 

 hand. In size the smallest individuals are approached only 

 by the smallest examples of crratica, in which species the greatest 

 size variation occurs. 



Measurements {in niilUntctcrs) 



71 Length of Length of Width of Length of Width of 



O body pronotum pronotum tegmen tegmen 



Florence, Arizona (12). 10.6-12 3.1-3.9 4.8-5.3 12-13.9 4.8-5.7 

 Phoenix, Arizona (7) . . 10-11.8 3.7-3.9 4.8-5.7 12.7-16.3 5-6.3 

 Yuma, California 11.8 3.9 5.6 14.7 6 



The striking features of the dextro-ventral concealed genital 

 plate of the male are described by Caudell. These are figured 

 in the present paper and serve readily to distinguish males of 

 the species. We note that in one specimen the minute tooth 

 at the side of the clubbed process is absent, this being apparently 

 of no diagnostic significance. 



The interocular width in the males at hand varies from four- 

 fifths as wide to one and one-fifth times as wide as that between 

 the ocelli. The majority of specimens have these dimensions 

 subequal. 



All of the males before us have the dark markings of the pro- 

 notum sharply contrasting and the tegminal maculations dis- 

 tinct. The species does not appear to develop a striking intensive 

 type of coloration, such as occurs in apacha. 



The female sex of genitalis is apparently unknown. 



TRANS. AM. ENT. SOC, XLVI 



