FLOWERING PLANTS AND FERNS OF ARIZONA 471 



15. Pubescence of the pods, if any, relatively short and more or less 



appressed (18). 



18. Pods stipitate, the stipes 2 1 2 to 3 times as Ions a> the calyx: 



stems and the lower surface of the leaflets sparsely strigose; 



leaflets mostly broadly obovate: pods broadly ovoid, 15 to 20 



mm. long 45. A. ampullarius. 



18. Pods sessile or nearly so (19). 



19. Calyx 4 to 7 mm. long, campanulate or cylindric-campanulate: 

 corolla 8 to 15 mm. long; pods 10 to 15 mm. long; leaflets 

 2 to 4 mm. wide (20). 

 20. Pods rather promptly dehiscent, not rugose-veiny, deeply 

 grooved toward the base on each side of the very promi- 

 nent ventral suture: leaflets acute or acutish at apex; 

 calyx 5 to 7 mm. long; corolla 10 to 15 mm. long. 



8. A. COXFERTIFLORUS. 



20. Pods indehiscent or tardily and incompletely dehiscent, 



rugose-veiny, not deeply grooved on the ventral side, the 

 ventral suture not prominent: leaflets rounded or obtuse 

 at apex: calyx less than 5 mm. long; corolla about 8 mm. 



long 28. A. accumbex-. 



19. Calyx 7 mm. long or longer, cylindric. corolla usually at lea>t 



15 mm. long: pods rarely less than 15 mm. long (except in 



A. castaneaeformis), indehiscent; leaflets commonly 5 mm. 



wide or wider, elliptic to obovate, not more than 3 times as 



long as wide (21). 



21. Leaflets glabrous or sparsely strigose above (22). 



22. Racemes little or not surpassing the leaves, usually dense 

 in flower; calyx hairs prevailingly white: pods glabrous, 

 ovate or oblong-ovate in outline, acuminate at apex, 

 15 to 20 mm. long 14. A. remulcus. 



22. Racemes greatly surpassing the leaves, rather loose in 



flower: calyx hairs prevailingly black; pods strigose, 

 oblong-lanceolate in outline, abruptly acute at apex, 



20 to 40 mm. long 15. A. chloridae. 



21. Leaflets strigose to sericeous on both faces, usually rather 

 densely so (23) . 



23. Pods straight, oblong or oblong-lanceolate in outline. 



18. A. ve>pertixu>. 

 23. Pods more or less curved (24 . 



24. Pods broadly ovate in outline, very asymmetric, not 

 more than twice as long as their greatest diameter. 



17. A. CA.-TAXEAEFORMIS. 



24. Pods oblong-lanceolate to oblong-ovate in outline, 3 or 

 more times as long as their greatest diameter (25). 

 25. Calyx in flower 10 to 14 mm. long; pods pilose with 

 short, more or less kinky, subappressed hairs, 

 slightly curved, not tapering at base. 



13. A. PEPHRAGMEXUs. 



25. Calyx in flower usually not more than 10 mm. long; 



pods appressed-pubescent, strigose to sericeous (26). 



26. Pods strongly curved, sometimes forming nearly a 



semicircle, acuminate at both ends, often so 



much narrowed at base as to appear stipitate. 



12. A. AMPHIOXV>. 



26. Pods moderately curved, obtuse or acutish at base. 



16. A. CURTILORU-. 



1. Plant caulescent, the stems leafv well above the base and usually more than 

 10 cm. long (27). 

 27. Leaflets and stipules rigidly spine-tipped; leaflets subulate, about one- 

 eighth as wide as long: flowers very few, in axillary clusters shorter 

 than the leaves: pods 1-celled, lanceolate in outline __ 1. A. impensus. 

 27. Leaflets and stipules not risidlv spine-tipped but sometimes sharply cuspi- 

 date (28). 

 28. Walls of the pod transversely ridged and furrowed, at least in pressed 

 specimens (29). 

 29. Ridges of the pod rather hard and sharp-edged, the pods completely 

 2-celled, not more than 4 mm. long; seeds usually only 2. 



73. A. DISPEBMUS. 



