PEA FAMILY 503 



long; corolla ochroleucous, 12 mm. long. A. urceolatus Greene. Mountains: 

 Colo. Submont. Je. 



30. XYLOPHACOS Rydb. Sheep-pod. 



Perennial herbs, mostly low, usually copiously hairy, often canescent, with 

 short stems. Leaves alternate, with nearly free and distinct stipules; leaflets 

 few or more numeroiis, entire. Flowers in short, often subcapitate racemes. 

 Calyx cylindric; lobes much shorter than the tube. Corolla purple, rarely 

 ochroleucous or in one species crimson; banner narrow, slightly longer than the 

 wings. Stamens 10; filaments diadelphous; anthers alike. Pods fusiform, or 

 ovoid, leathery or woody, 1-ceIIed, without partition; the lower suture sometimes 

 slightly sulcate. Seeds numerous. 



Pod strigose or glabrous. 



E.KOcarp of the fruit not spongy; stem evident, but often short. 

 Pod more or less curved. 



Plant sparingly hairy or glabrous, scarcely canescent; stem usually more or 

 less elongate.' 

 Caly.x-tube about 10 mm. long, white-hairy; plant sparingly silky. 



1. X. stipularis. 

 Caly.x-tube 5-8 mm. long, black-hairy; plant strigose or glabrous. 



Pod 2-2. .5 cm. long, abruptly acute at both ends. 2. X. cuspidocarpus. 

 Pod 2.5-4 cm. long, long-acuminate at both ends. 3. X. cibnrius. 

 Plant densely canescent, with white silky appressed hairs; stem low, decumbent. 

 Pod elongate: dorsal suture distinctly sulcate. 

 Pod tapering at the base, not very tliick. 



Calyx-teeth subulate, about half as long as the tube. 



4. X. aragalloides. 

 Calyx-teeth less than half as long as the tube. 5. X. amphioxys. 

 Pod not tapering at the bases. 



Calyx with black hairs; leaflets oval; corolla white or cream-colored. 



6. X. eurckensis. 

 Calyx without black hairs; leaflets roimded-obovate ; corolla purple. 



7. X. Shortianus. 

 Pod short-ovoid; neither suture distinctly sulcate. 



Pod mottled. 



Pod very strongly ciu-ved and vertically flattened at the middle; 



leaflets oval, acute, strigose. S. X. Zionis. 



Pod slightly curved; leaflets oblong, rounded or truncate at the 

 apex, villous. 9. X. puniceus. 



Pod not mottled, slightly curved and turgid. 



Calyx-teeth subulate, about half as long as the tube; leaflets oblong- 

 oval. 10. A. argophyllus. 

 Calyx-teeth lanceolate, one-foiu-th as long as the tube; leaflets 

 obovate. 11. X. uinlensis. 

 Pod straight or nearly so; plant canescent. 



Pod obcompressed, somewhat triangular; ventral suture only prominent. 



12. X. vesperlinus. 

 Pod compressed; both sutures prominent. 



Corolla purple; calyx with black hairs. 1.3. X. missouricnsis. 



Corolla wMte or oclu"oleucous with pxirple-tipped keel; calyx without black 

 hairs. 14. X. cymboides. 



Exocarp of the fruit spongy at least in age; plant sub-acaulescent, less than 5 cm. 

 high. 

 Leaflets 7-11, rounded-obovate, obtuse. 15. X. pygmaeus. 



Leaflets 1-3, broadly lanceolate, acute. 16. X. miisinensis. 



Pod villous. 



Pod densely woolly, short-ovoid; plant canescent. 

 Pubescence of the leaves strictly appressed. 



Leaflets elliptic to obovate: caly.x-teeth one-fourth as long as the tube. 

 Leaflets obovate, obtusish; pedimcles much shorter than the leaves. 



17. X. Newberryi. 

 Leaflets oblanceolate, acute; peduncles about equalling the leaves. 



18. X. consectus. 

 Leaflets broadly obovate-cuneate, rounded, truncate, or retuse at the apex;- 



calyx-teeth half as long as the black- villous tube. 19. X. Watsonianus. 



Pubescence of the leaves loosely woolly. 



Stems 1 dm. long or less; bracts ovate or oblanceolate, only slightly exceed- 

 ing the pedicels. 

 Leaflets broadly obovate, rounded at the aoex; plant densely floccose. 



20. X. utahensis. 

 Leaflets oblanceolate or oblong, acute; plant hirsute- villous. 



Corolla ochroleucous; only the keel purple-tipoed. 21. X. Purshii. 

 Corolla purple. 22. X. glareosus. 



Stems 2-4 dm. high; bracts subulate, at least half as long as the calyx. 



23. X. inflexus. 

 Pod sparingly villous, elongate; plant not canescent. 24. X. Parry i. 



