FABACEAE. 211 



Pod over 1.2 cm. long. 



Pod 2-2.5 cm. long ; corolla ochroleucous. 5. P. Candolleana. 



Pod 12-15 ni"i- long; corolla purple. 6. P. cerussata. 



Pod 3-12 mm. long. 



Pod ovoid ; plant 3-6 dm. high ; raceme many-flowered. 



7. P. Bodinii. 

 Pods ellipsoid ; plant usually less than 3 dm. high ; raceme few-flowered. 

 Plant cespitose ; stem slender, 1-2 dm. high, slender; leaflets 0.5-1 cm. 



long. 8. P. pauciHora. 



Plant pulvinate-cespitose, almost stemless ; leaflets minute. 



9. P. humillima. 

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

 obovate. lo. P. elatiocarpa. 



1. Phaca Eastwoodiae (Jones) Rydb. {Astragalus Preussii sulcatus 

 Jones; A. Easlzvoodiae Jones) In Utah and Colo. — Westwater. 



2. Phaca longifolia (Pursh) Nutt. {A. pictus Ulifolius A. Gray) On 

 sandy soil from S. D. and Wyo. to Colo, and N. M. — Salida ; Manitou ; Mani- 

 tou Junction. 



3. Phaca picta A. Gray. {A. pictus foliosus A. Gray) In sandy soil from 

 Colo, and Utah to N. M. — Denver; Colorado Springs. 



4. Phaca artipes (A. Gray) Rydb. {Astragalus artipes A. Gray) In the 

 mountains of Colo. — Alt. 7000-8000 ft. — Cerro Summit ; Cedar Edge ; Leroux 

 Creek. 



5. Phaca Candolleana H. B. K. {Astragalus triAorus A. Gray) In dry 

 places from Colo, to N. M. and Calif. ; also Mex. — Caiion City. 



6. Phaca cerussata (Sheld.) Rydb. {Astragalus ccrusatus Sheld.) Moun- 

 tain sides in Colo. — Cation City, Fremont Co. 



7. Phaca Bodinii (Sheld.) Rydb. {Astragalus Bodinii Sheld.) In val- 

 leys from Mont, to Neb. and Colo.— Alt. 4000-5000 ft. — North Park, Larimer 

 Co. 



8. Phaca pauciflora Nutt. {A. leptaleus A. Gray) In the mountains of 

 Colo. — Alt. 7000-10,000 ft. — Mt. Harvard; North Park, Larimer Co.; Como, 

 South Park ; Gunnison ; Laramie River. 



9. Phaca humillima (A. Gray) Rydb. {A. humillimus A. Gray) On arid 

 table-lands of Colo.— Mesa Verde, near Mancos River. 



10. Phaca elatiocarpa (Sheld.) Rydb. {Astragalus lotiAorus brachypus 

 A. Gray; A. elatiocarpus Sheld.) On plains from Minn, to Ass. to Mo., 

 Tex. and Calif. — Cafion City; Colorado Springs. 



11. Phaca Wetherillii (Jones) Rydb. {Astragalus Wetherillii Jones) 

 Dry hills and mesas of Colo. — Grand Junction. 



26. OROPHACA Britton. 



Densely cespitose; flowers 8-10 mm. long; inflorescence not exceeding the leaves. 



Flowers about 10 mm. long; pods puberulent. i. O. tridactylica. 



Flowers about 8 mm. long ; pods hoary. 2. O. aretioides. 



Broadly cespitose with prostrate branches ; flowers about 6 mm. long ; peduncles 



usually exceeding the leaves ; pods hoary. 3. O. sericea. 



I. Orophaca tridactylica (A. Gray) Rydb. {Astragalus tridactylicus A. 

 Gray) On plains and hills of Colorado. — Alt. 5000-6000 ft. — Livermore; 

 St. Vrain's Canon; Ft. Collins; plains near Denver; foot-hills west of Ft. 

 Collins; east of Black's Lake; near New Windsor. 



