FLOWERING PLANTS AND FERNS OF ARIZONA 473 



44. Pods straight to strongly arcuate but not forming more than a 



semicircle (except sometime- in A. palans), not more than 



30 mm. long (45). 



45. Keel noticeably produced at a right angle to the claws; 



stems decumbent to nearly prostrate: pools linear or 



linear-lanceolate in outline, straight or >lightlv falcate 



(46 . 



46. Prolongation of the keel obtuse, horizontal; leaflets 



silvery-strigo.-e on both faces 'rarely glabrate above), 



linear or lance-linear, 5 or more times as long as wide; 



keel nearly as long as the banner: pods shallowly 



grooved dorsally 65. A. arizonk :us. 



46. Prolongation of the keel sharply acuminate, often ascend- 



ing at apex: leaflets glabrous above, elliptic to obovate, 

 less than 3 times as long as wide; keel much shorter 

 than the banner: pods deeply grooved dorsally. 



66. A. XOTHOXYS. 

 45. Keel not noticeably produced, rounded to acutish at apex; 

 pods curved or falcate 47 . 



47. Pedicels recurved at or very soon after anthesis, the 



flowers nodding: plants perennial: leaflets glabrate 

 above, sparsely strigose beneath: corolla not more than 

 8 mm. long: pods more or less falcate (48). 

 48. Racemes loosely few-flowered; corolla apparently 

 purplish; pods more than 15 mm. long. 



52. A. REcuRvrs. 



48. Racemes densely many-flowered; corolla whitish: pods 



less than 15 mm. long 67. A. hartwegii. 



47. Pedicels not recurved at anthesis but sometimes so in 

 fruit (49) . 



49. Plant annual: corolla not more than 7 mm. long; pods 



not more than 3 mm. wide: leaflets strigose on both 



faces 68. A. xfttalljaxf-. 



49. Plants perennial; corolla 10 mm. long or longer; pods 4 

 to 5 mm. wide (50). 

 50. Leaflets glabrous on both faces or very sparsely 

 strigose beneath: .-tern- 15 cm. or longer; corolla 

 15 to 20 mm. long: walls of the pods papery. 



54. A. PALANS. 



50. Leaflet < strigose on both faces: stems not more than 



10 cm. long: corolla 12 mm. long: walls of the pods 



coriaceous 64. A. exsiformfs. 



30. Pods 1-celled, the lower suture sometimes introverted but the septum, 

 if any. not extending halfway across the cavity (51 . 

 51. Length of the pod more than 3 times the greatest diameter i52). 

 52. Pods 3- or 4-winged (with a wing in the center of each valve and on 

 one or both of the sutures), strongly arcuate, the walls woody; 

 plant glabrous or nearly so: leaflets narrowly linear. 



21. A. TETRAPTERFS. 



52. Pods not winged or strongly arcuate, the walls not wood}* but some- 

 times coriaceous (53 . 

 53. Stems prostrate or nearly so, very leafy: plant perennial: pods 



more or less falcate 24. A. hfmistratfs. 



53. Stems erect, ascending, or decumbent, if nearly prostrate, then 

 the plant annual (54 . 

 54. Plant a short -lived annual: corolla not more than 7 mm. long: 



pods falcate, not pendulous 68. A. nuttalmanus. 



54. Plant perennial: pods straight or nearly -. i ~>7) . 



55. Corolla usually less than 8 mm. long: pods pendulous, 

 - — ile or very nearly so; leaflet •< 7 to 15. 



4. A. WIXGATAXFS. 



55. Corolla 8 mm. long or longer (56") . 



56. Pods stipitate, barely so in .1. kaith ' 7 



57. Leaflets elliptic to broadly obovate: pods nol pendu- 

 lous, indehiscent or nearly so, the walls subcoriace- 

 ous; plant glabrous or very nearly so. 



46. A. PBEUSSII. 



