PEA FAMILY 139 



Leaflets present; racliis not produced. 



Stem canescent, 1-2 dm. liigh; calyx-teeth subulate. 



8. P. picta. 

 Stem glabrous or nearly so, 3-5 dm. high; calyx-teeth triangular. 



9. P. Cusickii. 

 Leaflets elliptic to broadly oval or obcordate. 



Plant glabrous. 10. P. artipes. 



Plant canescent. 11. P. Hookeriana. 



Pod sessile. 



Pod more than 12 mm. long. 



Plant densely cespitose, almost stemless; pod 3.5-5 cm. long. 



12. P. megacarpa. 

 Plant distinctly caulescent and leafy; pod 3 cm. long or less. 



Whole plant glabrous. 13. P. Wardii. 



Plant, including the pods, pubescent. 



Calyx-teeth very short, scarcely one-tliird as long as the tube. 



14. P. subcinerea. 

 Calyx-teeth subulate, fully as long as the tube. 



Plant appressed-pubescent, cespitose and much branched. 

 Stem ascending. 



Inflorescence scarcely equalling the leaves; pod 2-2.5 cm. 



long; corolla ochroleucous. 15. P. Candolleana. 



Inflorescence exceeding the leaves; pod 12-15 mm . long; 

 corolla piu'ple. 16. P. cerussata. 



Stem decumbent. 17. P. serpens. 



Plant with short spreading pubescence; stem simple, elongate. 



18. P. Silerana. 

 Pod 8-12 mm. long. 



Stem slender and much branched, usually more than 1 dm. high; leaflets more 

 than 5 mm. long, flat, oblong, oval, or obovate. 

 Leaflets 5-11 pairs. 



Plant sUghtly strigose. 



Pod ovoid; plant 3-6 dm. liigh; racemes many-flowered. 



19. P. Bodinii. 



Pod ellipsoid; plant iisually less than 3 dm. high; racemes few- 

 flowered. 20. P. leptalea. 

 Plant densely hirsutulous. 18. P. Silerana. 

 Leaflets 4-6 pairs; plant more or less grayish-pubescent; pod globose-ovoid. 



21. P. microcystis. 

 Stem densely pulvinate-cespitose, with a thick caudex, only a few centimeters 

 high; leaflets minute, linear or lanceolate, conduplicate, 1-4 mm. long. 

 Racliis of the leaves not spinose; pod slightly puberulent, mottled, 1 cm. 



long. 22. P. jejuna. 



Rachis of the leaves spinose; pod wliite-pubescent, 4-6 mm. long. 



23. P. humiUima. 

 Upper suture of the pod straight or curved upwards, acute ; pod in cross-section obovate, 

 triangular-obovate, or slightly cordate. 

 Plant, including the pods, perfectly glabrous, 2 dm. high or more; pods stipitate, 

 somewhat leathery. 

 Corolla oclu-oleucous; calyx-teeth nearly equalling the tube. 24. P. Beckwithii. 

 Corolla purple; calyx-teeth much shorter than the tube. 25. P. arlemisiarum. 



Plant, including the pods, more or less hairy; pods sessile. 

 Pods much over 1 cm. long, usually not mottled. 



Pods strongly inflexed; flowers wliite or ochroleucous, tinged with purple. 



26. P. pubentissima. 

 Pods not strongly incurved ; upper suture straight or nearly so ; flowers ochro- 

 leucous. 

 Plant strictly annual. 



Plant cinereous, with short hairs ; pods puberulent. 27. P. annua. 

 Plant, including the pods, grajash hoary. 28. P. sabulonum. 



Plant perennial or at least biennial, cespitose, low. 



Flowers mostly subsessile in the axils of the leaves; racemes if ped- 

 uncled 2-3-flowered; leaflets mostly over 1 cm. long, appressed-hairy. 



29. P. elatiocarpa. ' 

 Flowers in peduncled several-flowered racemes; leaflets mostly less than 

 Icm.long, loosely hairy beneath, glabrate above. 30. P. loti flora. 

 Pods about 1 cm. long, mottled; plant diffusely cespitose. 31. P. sesquiflora. 



19. CYSTIUM Stev. 



Plant cespitose, less than 1 dm. high, canescent, nearly stemless; pod not ciirved. 



1. C. platytrope. 

 Plant with elongate stems, 1-4 dm. high. 



Plant silvery canescent-strigose; corolla pinkish. 2. C. Coulteri. 



Plant glabrous or slightly strigose, not silvery. 



Corolla purple. " 3. C. diphysum. 



Corolla white or yellowish, purple only at the tip. 

 Pod more than 1.5 cm. long. 



Pod short-ovoid, only slightly cm-ved. 4. C. heliophilum. 



Pod elongate-ovoid, strongly curved. 



Calyx-teeth at least half as long as the tube; corolla 8-9 mm. long. 



5. C. lentiginosum. 



