PAPILIONACEAE. 533 



Tribe 4. TRIFOLIEAE. 



Flowers spiked, or capitate; pods curved, or coiled. 10. Mcdicago* 



Flowers in long racemes; pods coriaceous. u. Melilotus. 



Flowers capitate or umbelledj pods straight, membranous. 12. Trifolium* 



Tribe 5. LOTEAE. 



A. single genus in our area. 13. Lotus. 



Tribe 6. PSORALEAE. 



Leaves digitately 3-5-foliolate, or pinnately 3-foliolate. 14. Psoralea. 



Leaves pinnately 5-many-foliolate. 



Stamens 10 or 9, monadelphous, at least at the base. 



Corolla of only i petal (the standard). 15. Amorpha. 



Corolla of 5 petals, the wings and keel united to the filament-tube. 



1 6. Par os el a. 

 Stamens only 5, monadelphous. 17. Kuhnistera. 



Tribe 7. GALEGEAE. 



Standard very broad, ovate or orbicular. 

 Herbs; leaves odd-pinnate. 



Pod 4-angled in our species. 18. Indigofera. 



Pod flat. 19. Cracca. 



High-climbing woody vines. 20. Bradleya. 



Trees or shrubs. 21. Robinia. 



Herbs ; leaves evenly pinnate. 22. Sesban* 



Standard narrow; our species all herbs. 



Pod not prickly; foliage not glandular-punctate. 

 Keel of the corolla blunt. 



Leaves pinnate, rarely i-foliolate. 



Pod not flattened, swollen, or one or both sutures intruded. 

 Pod not much swollen, fleshy, leathery or papery. 



23. Astragalus. 



Pod much inflated, membranous. 24. Phaca. 



Pod flat, both sutures prominent externally. 25. Homalobus. 



Leaves 3-foliolate. 26. Orophaca. 



Keel of the corolla acute. 27. Aragallus. 



Pod prickly; foliage glandular-punctate. 28. Glycyrrhiza. 



Tribe 8. HEDYSAREAE. 



Leaves odd-pinnate. 



Flowers purplish, umbellate. 29. Coronilla. 



Flowers purple or white, racemose 30. Hedysarum. 



Flowers yellow, small. 31. JEschynomene. 



Leaves 4- foliolate or 2-foliolate. 33. Zornia. 

 Leaves 3-foliolate, the terminal leaflet stalked. 



Flowers yellow. 32. Stylosanthes. 



Flowers purple, blue or white. 



Pod of several joints; leaflets stipellate. 34. Meibomia. 



Pod of i or 2 joints; leaflets not stipellate. 35. Lespedcza* 



Tribe 9. VICIEAE. 



Style slender, with a tuft of hairs at the summit. 36. Vicia. 



Style flattened, bearded along the inner side. 37. Lathyrus. 



Tribe 10. PHASEOLEAE. 



Style bearded along the inner side; rachis not thickened at the insertion of the flowers ; 



keel of corolla not curved nor coiled. 39. Cliton'a. 



Style glabrous, or slightly pubescent below; keel of corolla not curved nor coiled. 

 Standard spurred at the base. 38. Bradburya. 



Standard not spurred. 



Flowers blue, purple, purplish, or white. 



Leaves odd-pinnate ; leaflets 5-7. 41. Apios. 



Leaves 3-foliolate, rarely i-foliolate. 



Calyx tubular, not bracteolate. 40. Falcata. 



Calyx short, bracteolate. 42. Galactia. 



Flowers yellow. 43. Dolicholus. 



Style bearded along the inner side; rachis thickened at the insertion of the flowers. 

 Keel of the corolla spirally coiled ; flowers racemed. ' 44. Phaseolus. 



Keel strongly incurved; flowers purple, capitate. 45. Strophostyles. 



Keel short, slightly incurved; flowers yellowish, capitate. 46. Vigna. 



