50 PROCEJIJDINGS OF THE NATIONAL ]MUSEUM vol. 90 



21. Anellus narrowed posteriori}^; clasper very slender (fig. 159) 



clemensella (Chambers) (p. 68) 

 Anellus not appreciably narrowed posteriorly; clasper strong 



(figs. 163, 164) ' 22 



22. Anellus with a narrow, biramous, strongly sclerotized median 



area pulvipennella (Clemens) (p. 76) 



Anellus without such sclerotized area (figs. 163, 180) 23 



23. Lateral lobes of anellus nearly attaining posterior edge of cen- 



tral plate (fig. 180) cajonensis, new species (p. 82) 



Lateral lobes of anellus not nearly attaining posterior edge of 



central plate (fig. 163) eupatoriiella (Chambers) (p. 74) 



24. Anellus strongly constricted anteriorly; harpe abruptly narrowed 



beyond clasper (fig. 160) atrodorsella (Clemens) (p. 70) 



Anellus not strongly constricted anteriorly and harpe not 

 abruptly narrowed beyond clasper (fig. 188) 



latipalpella Barnes and Busck (p. 118) 



25. Distal half of aedeagus much more slender than proximal half 



(fig. 165a) walsinghamella (Busck) (p. 78) 



Aedeagus of about equal thickness throughout its length (fig. 



158a) muricolorella (Busck) (p. 64) 



26. Clasper nearly attaining costa of harpe (figs. 162, 178) 27 



Clasper not reaching much beyond middle of harpe (figs. 166, 



172, 182) 28 



27. Posterior edge of anellus convex (fig. 178) clarkei Keifer (p. 66) 



Posterior edge of anellus not convex (fig. 162) 



pteleae Barnes and Busck (p. 72) 



28. Aedeagus long, slender (fig. 166a) rosaciliella (Busck) (p. 83) 



Aedeagus stout (figs. 172a, 182a) 29 



29. Anellus with a narrow, longitudinal, weakly sclerotized median 



area; cucullus rather pointed (fig. 182) pallidella (Busck) (p. 88) 



Anellus without such median area; cucullus rounded (fig. 172) 



senicionella (Busck) (p. 107) 



30. Clasper twisted (fig. 168) novi-ravxndi (Walsingham) (p. 87) 



Clasper not twisted (fig. 167, etc.) 31 



31. Clasper reaching at least three-fourths of the way to costa of 



harpe (figs. 170, 187) 32 



Clasper reaching to or slightly beyond middle of harpe (fig. 167, etc.).. 34 



32. Clasper straight (figs. 170, 187) 33 



Clasper definitely curved distally (fig. 176)__oregonensis, new species (p. 65) 



33. Clasper stout (fig. 187) amissella (Busck) (p. 117) 



Clasper slender (fig. 170) nigrinotella (Busck) (p. 101) 



34. Posterior edge of anellus concave (figs. 171, 179) 35 



Posterior edge of anellus not concave (figs. 167, 169, 175, 189) 36 



35. Clasper slender, reaching slightly beyond middle of harpe (fig. 



171) argillacea (Walsingham) (p. 98) 



Clasper stout, not reaching beyond middle of harpe (fig. 178) 



dimorphella, new species (p. 97) 



36. Anellus nearly round (figs. 169, 189) 37 



AneUus roughly rectangular (fies. 167, 175) 39 



37. Posterior margin of anellus with shallow cleft; cucullus sharply 



pointed (fig. 189) sanguinella (Busck) (p. 123) 



Posterior margin of anellus without any trace of a median cleft; 



cucullus dull-pointed (fig. 169) 38 



