160 American Midland Naturalist Monograph No. 2 



20. Fruit a legume. 



23. Leaflets not slipellate. 



24. Flowers in heads; pods small, often mcluded m the calyx, 



1-6-seeded, not stipitate; stamens diadelphous 



1 I . TrifoUum 



24. Flowers m racemes, or solitary. 



25. Flowers whitish (or yellow) in racemes; stamens dis- 

 tinct; pods stipitate, turgid or inflated; plants tending 



to turn black in drying 8. Dapiisia 



25. Flowers pink, solitary; stamens diadelphous; pods 



linear, somewhat compressed, not stipitate 



14. Hosacl^ia 



23. Leaflets stipeilate. 



26. Style glabrous; plants twining; flowers purplish or white. 



27. Calyx usually 5-toothed, not bracteolate; leaflets ovate 



35. Amphicarpa 



27. Calyx deeply 4-cleft, subtended by a pair of bractlets; 



leaflets oval 36. Calactia 



26. Style pubescent on the upper surface. 



28. Flowers yellow; stems twining; leaflets ovate; pods 



10-20 cm. long 32. Vigna 



28. Flowers bluish or nearly white. 



29. Flowers 4-5 cm. long, solitary or in pairs in the 

 axils, pale blue and lilac, delicately veined; stem 



ascending or twining 34. Cliioria 



29. Flowers smaller, racemose or umbellate. 



30. Flowers in short sessile axillary racemes; stem 

 erect; pods straight or nearly so, almost sessile, 



somewhat flattened 31. C/licine 



30. Flowers in racemes or umbels en long axillary 

 peduncles; stems twining or trailing. 

 31. Flowers in long loose racemes; keel of the 



corolla spirally coiled; pods falcate 



30. Phaseolus 



31. Flowers few, in umbel-like clusters; keel of 

 the corolla strongly incurved but not 

 spirally coiled; pods straight or nearly so 



33. Slrophost\}les 



I 5. Leaves with 5 or more leaflets. 



32. Leaves punctate; corolla indistinctly or imperfectly papilionaceous; pods 

 1 -seeded, indehiscent. enclosed in the calyx. 

 33. Stamens 5; leaflets (in our species) 6-35 mm. \ons,.. .. ]S. Pelalosiemum 



33. Stamens 10 or rarely 9; leaflets (in our species) 4-6 mm. long 



]7.Ddca 



32. Leaves not punctate; corolla papilionaceous; pods several-seeded. 



34. Leaflets 5-11. 



35. Stems twining or climbing; leaflets 5-7 (rarely 3), ovate or ovate- 

 lanceolate; flowers brownish purple, in axillary racemes 



29. Apios 



35. Stem erect; leaflets 7-11, oblanceolale ; flowers blue (or pink or 



white), in terminal racemes 10. Lupinus 



34. Leaflets 11-31. 



36. Plants hoary-pubescent; flowers in terminal racemes 



19. Tephrosia 



36. Plants strigose to glabrous; flowers in axillary racemes or head- 

 like umbels. 



37. Flowers racemose; pods not 4-angled or jointed 



22. Astragalus 



37. Flowers umbellate, rose colored; pods Imear, 4-angled, jointed 

 23. Coronilla 



