HESPERIOIDEA OF AMERICA 39 



of equal length intermingled ; in Hesperia the palpi are strongly 

 upturned and very heavily and roughly clothed underneath with 

 long hairs, the scales being confined to the lateral basal portion." 



It is quite true that this furnishes a good basis for the sep- 

 aration of our species, and the general habitus of each group 

 is also distinctive, but I have unidentified species of the genus 

 from South America which have the habitus of Hesperia (sensu 

 B. & McD.) and the palpi of Pyrgus. It seems that the only 

 conclusion which will give a well founded classification is to 

 adopt the genus Hesperia of many European writers. 



I cannot expect unanimous approval of the sinking of Helio- 

 petes, but after examining all of the species carefully and com- 

 paring them with those of Hesperia I am unable to point out 

 any structure which does not find either its counterpart or a 

 similar tendency in the latter genus. The pattern of Hesperia 

 is easily traceable in ericetorum and domicella, both above and 

 below; in nivella, laviana and macmra the under surface is 

 puzzling, but the brown pattern may easily be a modification of 

 a superficial vestiture such as that found in syrichtus, while the 

 black marks are so scanty as to afford no comparison. 



Key to the species 



1. Upper surface of primaries with a broad white discal band or mostly 



white 8 



Band narrow and macular or not evident 2 



2. Spots of primaries subquadrate, well separated 3 



Spots crowded, slender; with an additional row of spots beyond cell. .6 



3. Primaries with a triangular white spot in the angle of vein 2 and the 



cell 4 



This spot absent centaureae 



4. Male with fold; subterminal spots on under surface of secondaries 

 deeply crescentic in most specimens, even when reduced in size . . ruralis 

 Male without fold; subterminal spots never deeply crescentic, usually 

 poorly defined 



5. Under surface of secondaries without distinct contrasts, whitish ; mark- 

 ings of upper surface usually reduced; a pale, glossy species, .scriptura 

 Under surface with contrasting markings; upper surface with macula- 

 tion rarely reduced; darker species xanthus, macdunnoughi 



6. Under surface of secondaries with two small submarginal lunules be- 

 tween veins 4 and 6 



These vague, fused with a marginal white patch or with each other 



tessellata 



