290 
NORTH AMERICAN MYRMOSIDAE 
Plate XXIII 
Male genitalia 
Figs. 21 to 26, 28 and 29 drawn by iSIiss Margaret iSIoles, from dry mounts, 
x30. 
Figs. 27 and 30 drawn by the author from a balsam mount, x 30. 
Fig. 21. — Brachycistis crassa Bradley; holotype; dextral aspect. 
Fig. 22.^ — Brachycistis crassa Bradley; holotype; dorsal aspect, right half. 
Fig. 23. — Brachycistis crassa Bradley; holotype; dextral aspect of left half. 
Fig. 24. — Brachycistis stygia Bradley; holotype; dextral aspect. 
Fig. 25. — Brachycistis stygia Bradley; holotype; dorsal aspect of right half. 
Fig. 26. — Brachycistis stygia Bradley; holotype; dextral aspect of left half. 
Fig. 27. — Brachycistis castanea Fox; homotype; dextral aspect, from slide 
mounted in balsam. 
Fig. 28. — Brachycistis eremi Bradley; para type; dextral aspect. 
Fig. 29. — Brachycistis eremi Bradley; paratype; dorsal aspect, right half. 
Fig. 30. — Brachycistis castanea Fox; paratype; dextral aspect of left half. 
Plate XXIV 
Male genitalia 
Drawn by Miss Margaret L. Moles, from dry mounts, x 38. 
Fig. 31. — Brachycistis thennarum Bradley; holotype; dextral aspect. 
Fig. 32. — Brachycistis thermarum Bradley; holotype; dorsal aspect of right 
half. 
Fig. 33. — Brachycistis thermarum Bradley; holotype; dextral aspect of left half. 
Fig. 34. — Brachycistis hrevis Fox; dextral aspect. 
Fig. 35. — Brachycistis noctivaga Bradley; holotype; dextral aspect. 
Fig. 36. — Brachycistis noctivaga Bradley; holotype; dorsal aspect of right half. 
Fig. 37. — Brachycistis noctivaga Bradley; holotype; dextral aspect of left half. 
Fig. 38. — Brachycistis brevis Fox; dorsal aspect of left half. 
Fig. 39. — Brachycistis nocticola Bradley; holotype; dextral aspect. 
Fig. 40. — Brachycistis nocticola Bradley; holotype; dorsal aspect of right half. 
Fig. 41. — Brachycistis arenivaga Bradley; holotype; dorsal aspect of right half. 
Fig. 42. — Brachycistis arenivaga Bradley; holotype; dextral aspect. 
Plate XXV 
INI ale genitalia 
Drawn by the author, from dry mounts, x 66. 
Fig. 43. — Brachycistis nevadensis Fox; holotype; dextral aspect of left half. 
Fig. 44. — Brachycistis carinata Fox; homotype; dextral aspect. 
Fig. 45. — Brachycistis dentata Bradley; holotype; dextral aspect of left half. 
Fig. 46. — Brachycistis triangidaris Fo.x; paratype; dextral aspect. 
Fig. 47. — Brachycistis triangularis Fox; paratype; dorsal aspect of uncus. 
Fig. 48. — Brachycistis elegantula Cockerell; paratype?; dextral aspect. 
Fig. 49. — Brachycistis inaequalis Fox; paratype; dextral aspect of left half . 
