REVISTON OF ELEODIINI BLAISDELL. 115 



the anterior tarsi in the male may bear a minute tuft of pubescence at 

 tip beneath; in the female the first joint is more or less thickened and 

 slightl}' more prominent ventrally than the others; in both sexes the 

 plantar groove is quite entire, except at the extreme apical margin of 

 the first joint; it is nearly entire at this point in some males. 



The pubescent tuft is most evident in extrlcata ; less in the other 

 species where it is darker in color and frequently quite obsolete. 



The subgenus is founded upon the female genital characters, which 

 are distinctive of the present aggregate. 



Suhgeneric genital characterK^ male. — Apicale of the edeagophore 

 triangular, sides sinuate, and the apex more or less attenuate; dorsal 

 surface more or less longitudinally grooved at middle. 



Female. — Genital segment quadrate to triangulo-parabolic, rather 

 thickly clothed Avith flying hairs. Dorsal plate of each valve oval- 

 oblong in outline, with the internal moiety reflexed and impunctate, 

 external onedialf broadl}^ and slightly reflexed; external border al- 

 most straight to more or less arcuate, passing into the apical margin 

 abruptly, forming an angle, or more gradually and arcuately so. 

 Apex small and membranous. 



Appendage large, more or less semi-elliptical, sometimes subconical, 

 flattened, Avith external border frequently continuing the line of the 

 external margin of the dorsal plate. Fossa narrow and transverse. 



Superior pudendal memjhrane. — Usually scarcely rugulose and 

 variable in length, long in extricata and letclwn., short in arcuata 

 and granidata. 



Dtstnhution. — Extrieata has a very extensive distribution, occur- 

 ring in Texas, New Mexico, Arizona, Nevada, Utah, Colorado, Kansas, 

 Nebraska, Wyoming, Idaho, Montana, Dakota, and eastern Oregon. 



Arcuata is only known to me from Arizona. 



Granulata., in Oregon, northern and eastern California, in the desert 

 regions ; and if determinations are correct, in New Mexico and Colo- 

 rado. If this be true, it will be found to occur in the intervening 

 States. 



Letcheri in western Nevada and vandykei in northeastern Cali- 

 fornia and Oregon, 



Ge}iealogy. — Arcuata and extricata have no doubt arisen from a 

 common ancestral ramus, and from the other division of the ancestral 

 trunk granulata and letcheri have had their origin. 



Extncata and granulata are no doubt the older stock, and are at 

 present diverging at different parts of their distributional area into a 

 considerable number of incipient races, and continued collecting and 

 study will bring to light and differentiate many more. 



