Part 5, 1929] FABACEAE: GALEGEAE 289 



Pod slightly silicate on the lower suture, transversely veined; leaflets narrowly 



linear. 1. M. parviflorus. 



Pod flattened on the lower suture, cross-ridged; leaflets linear-oblong or linear- 



cuneate, truncate or emarginate. 2. M. gracilis. 



1. Microphacos parviflorus (Pursh) Rydb. Bull. Torrey Club 

 40:51. 1913. 



Dalea parviflora Pursh, Fl. Am. Sept. 474. 1814. 



Psoralea parviflora Poir. in Lam. Encyc. Suppl. 4: 590. 1816. 



Phaca parvifolia Nutt.; T. & G. Fl. N. Am. 1: 348. 1838. 



Astragalus gracilis A. Gray, Proc. Am. Acad. 6: 202. 1864. Not .4. gracilis Nutt. 1818. 



Astragalus parvifolius Nutt.; A. Gray. Proc. Am. Acad. 6: 202, as synonym. 1864. 



Tragacanlha parviflora Kuntze, Rev. Gen. 941. 1891. 



Astragalus parviflorus MacM. Metasp. Minn. Valley 325. 1892. Not A. parviflorus Lam. 1783. 



Phaca gracilis MacM. Metasp. Minn. Vallev 325, as synonym. 1892. 



Microphacos gracilis Rydb. Bull. Torrey Club 32: 663, in part. 1906. 



A perennial, with a woody root; stems several, the lower part often subterranean, from 

 prostrate to decumbent or ascending, the upper portion erect, flexuose, slender, 3-6 dm. high, 

 branched, strigose; leaves ascending, 3-7 cm. long; stipules deltoid, 1-3 mm. long, the lower 

 connate; leaflets 5-9, narrowly linear, 1-2.5 cm. long, 1-2 mm. wide, glabrous above, sparingly 

 strigose beneath ; peduncles 4— 10 cm. long, slender; racemes 3-10 cm. long, lax; bracts lanceo- 

 late, 1 mm. long; pedicels 1 mm. long; calyx strigose, the tube 1.5 mm. long, and as broad, the 

 teeth deltoid, 0.5 mm. long; corolla purplish, 5-6 mm. long; banner obovate, strongly arched 

 below the middle; wings shorter, the blade oblanceolate, falcate, with a rounded spreading 

 auricle; keel-petals still shorter, the blade broadly lunate, strongly incurved toward the 

 rounded apex; pod sessile, obliquely ovoid, cross-ribbed, 5-6 mm. long, 2 mm. wide, 3 mm. thick, 

 the cross-section reniform, the upper suture acute, the lower sulcate; seeds usually 2, obliquely 

 round-reniform, 2 mm. long. 



Type locality: Banks of the Missouri (perhaps South Dakota]. 

 Distribution: South Dakota to Texas, Colorado, and Wyoming. 



Illustrations: M. E. Jones, Rev. Astrag. pi. 43, f. 152; Britt. & Brown, 111. Fl./. 2140; ed. 2. 

 /. 2551; Fl. Neb. 21: pi. 9, /. 1-5; Clements, Rocky Mt. Fl. pi. 29. /. 20. 



2. Microphacos gracilis (Nutt.) Rydb. Bull. Torrey Club 

 32:663. 1906. 



Astragalus gracilis Nutt. Gen. 2: 100. 1818. 



Astragalus microlobus A. Gray, Proc. Am. Acad. 6: 203. 1864. 



Tragacanlha microloba Kuntze, Rev. Gen. 946. 1891. 



Microphacos microlobus Rydb. Bull. Torrey Club 32: 663. 1906. 



Astragalus parviflorus microlobus M. E. Jones, Rev. Astrag. 193. 1923. 



A perennial, with a woody root; stems decumbent at the base or ascending, branched and 

 flexuose, strigose-canescent, 2-5 dm. high; leaves mosdy spreading, 3-8 cm. long; stipules 

 deltoid, 2-3 mm. long; leaflets 11-15, linear or oblong, 5-15 mm. long, 1-3 mm. wide, glabrous 

 above, strigose beneath, rounded, truncate or retuse at the apex; peduncles 3-8 cm. long; ra- 

 cemes 4-8 cm. long; bracts lanceolate, 1 mm. long; calyx strigose, the tube 1.5 mm. long, the 

 teeth deltoid, 0.5 mm. long; corolla purple, 7-S mm. long; banner obovate, strongly arched 

 below the middle; wings obliquely obovate, falcate, with a rounded auricle, rounded at the 

 apex; pod obliquely ovoid, cross-ribbed, grayish-strigose, 7-9 mm. long, 2.5 mm. wide, and 

 4 mm. thick, the upper suture acute, the lower concave, the cross-section reniform; seeds 

 usually 2, brown, obliquely round-reniform, 2.5 mm. long. 



Typk locality: " From White River to the mountains, on the plains of the Missouri " [South 

 or North Dakota]. 



Distribution: South Dakota, Oklahoma, New Mexico, Utah, and Montana. 



Illustrations: M. E. Jones, Rev. Astrag. pi. 43; Britt. & Brown, 111. Fl. /. 2141; Fl. Neb. 21:/. 

 6-9. 



38. XYLOPHACOS Rydb.; Small, Fl. SE. U. S. 619, 1332. 1903. 



Perennial herbs, mostly copiously pubescent, usually low, often subacaulescent. Leaves 

 pinnate, the stipules nearly free, the leaflets entire-margined. Flowers in dense, short, some- 

 times head-like racemes. Calyx cylindric, the lobes shorter than the tube. Corolla purple, 



