376 



7. Ground color pure white. Mid tibiae with ri well developed median 



ti, f t clliottii 



Ground color otherwise or mid tibae with only a trace of the median 

 tuft S 



8. Primaries tawny, yellowish, or grayish ochreous, expanse less than 

 20 mm. or with spot nt base of cleft small, usually rounded, and the 

 only conspicuous discal mark. If gray powdered and small, abdomen 



with dorsal dots. Secondaries not contrastingly dark 9 



Not such species !•' 



9. Fringes dark at apex of lobes of primaries 10 



Fringes evenly colored some occidcntalis 



10. Palpi with dark scales on outer surface 1- 



Palpi entirely whitish 11 



11. Primaries yellowish. Expanse under 18 mm. Blackish-brown fringes 

 at tip of first lobe conspicuous, apex of second lobe with fringes scarcely 



darkened tinctus 



Primaries more tawny. Expanse 18-22 mm. Dark fringe at tips of 

 both lobes cocUisc 



12. Expanse usually under 20 mm. Dark fringes at apex of second lobe 



almost equally extensive on costal and outer margins some iobales 



Expanse usually well over 22 mm. Dark fringes of second lobe mostly 



on costal margin some kclianlhi 



13. Small or moderate species, primaries whitish, yellowish, grayish or och- 

 reous, usually rather coarsely powdered wMth dark scales. Either pale, 

 without extensive and contrasting pattern, or with dot at base of cleft 

 the only conspicuous discal mark. Mid tibiae with no more than a trace 



of median tuft 1"* 



Not such species. Either over 25 mm. expanse, with an evident median 

 tuft on mid tibiae, or with nebulous, contrasting gray brown marks on 



prmiarics 



21 



Inner margin of first lobe of primaries rather broadly white, contrast- 

 ing with the dark fringe intcgratus 



Without such a stripe, but sometimes with entire lobe paler than fringe 15 

 Secondaries dark, primaries yellowish with discal dot, varying to dark, 

 smooth gray with yellowish subcostal line ending opposite base of cleft. 

 This species has no definite costal spot over base of cleft, but the dark 



shade at this point sometimes approximates a spot some corvus 



Not such species lo 



Longer spur of first pair on hind tibiae reaching over half way to end 



of joint 1' 



This spur reaching less than half distance to end of tibia 18 



Primaries white with scattered brownish scales cadinus 



Primaries more or less ochreous with dark brownish irroration. discal 



dot conspicuous some iubatcs 



Head with a definite white patch between antennae 19 



Without such a patch ; head evenly coloured or nearly so 20 



