HESPERIOIDEA OF AMERICA 59 



page 106, at the same time dividing it and naming one part 

 Dalla. Such differences as he mentions between the two seem 

 to be slight and transitional through the series of species in- 

 cluded, and I therefore sink Dalla. The description of Dalla 

 does not apply to our species as well as Mabille's diagnosis of 

 Butleria, so if the genera be separated again there is a possi- 

 bility that Butleria, and not Dalla will still be applicable in 

 our region. 



Key to the species 



Under surface of secondaries immaculate pirus 



With a number of small pale spots microsticta 



With a few large spots polingi 



1. BUTLERIA PIRUS 



Pholisora pirus Edw., Field and Forest in, 119, 1878. 

 Colorado, Utah, Arizona; June, July. 



2. BUTLERIA MICROSTICTA 

 Butleria microsticta G. & S., Biol. Cent.-Am., Rhop. n, 464, pi. 92, ff, 1, 

 2, 3, 1900. 

 I have seen no specimens; the species is said to occur near the Mexican 



border. 



3. BUTLERIA POLINGI 



Pyrgus polingi Barnes, Can. Ent. xxxn, 44, 1900. 

 Arizona, June and July. 



GROUP B 

 Key to the genera 



1. Wings broadly rounded Ancyloxijpha, 



Wings more or less trigonate 2 



2. All wings trigonate; male without stigma; club of antennae 



about as long as shaft • • • Oarisma 



Males with stigma; secondaries, at least, rounded; club not 

 as long as shaft ^ 



3. Secondaries rounded, primaries trigonate; club small 



Copaeodes 



Outer margin of primaries more oblique and rounded ; club 

 large, relatively long Adopaea 



