Part 2, 1920] FABACEAE: PSORALEAE 129 



other petals oblong, 3 mm. long, the claws less than 1 mm. long; pod broadly obliquely obavate, 

 nearly orbicular, villous. 



Type locality: Texas. 



Distribution: Texas. 



Illustrations: Moric. PI. Nouv. Am. pi. 44. 



20. Petalostemon emarginatus T. & G. Fl. N. Am. 

 1:311. 1838. 



Kuhnistera emarginata Kuntze, Rev. Gen. 192. 1891. 



An annual, branched at the base; stems decumbent at the base, 2-5 dm. long, usually 

 simple, glabrous, terete; leaves 2-5 cm. long, spreading; stipules subulate; leaflets 13-17, 

 cuneate or oblong-cuneate, 2-7 mm. long, emarginate at the apex, glabrous, verdigris-green 

 above, minutely glandular-dotted beneath; spikes oblong or cylindric, long-peduncled, in 

 fruit 1-3 cm. long, about 1 cm. thick ; bracts obovate, abruptly acuminate, villous with glabrate 

 tips; calyx villous, 3 mm. long, oblique; lobes lanceolate, acuminate, fully equaling the tube; 

 corolla deep-pink; blade of the banner broadly rectangular-oblong, retuse or truncate at the 

 apex, truncate at the base, 2.5 mm. long, shorter than the claw; blades of the other petals 

 oblong, rounded at the apex, 2.5 mm. long, the claws short; pod obliquely obovate, somewhat 

 lunate, villous above. 



Type locality: Texas. 

 Distribution : Texas. 



21. Petalostemon exilis A. Gray, PI. Wright. 2: 41. 1853. 



Kuhnistera exilis Kuntze. Rev. Gen. 192. 1891. 



A slender annual; stem simple or somewhat branched, glabrous; leaves scattered, 3-5 

 cm. long, ascending; stipules subulate; leaflets linear, acute, 1-3 cm. long, 1-2.5 mm. broad; 

 spike long peduncled, cylindric, in fruit 6 mm. thick, 1-4 cm. long; bracts ovate, acuminate, 

 sparingly pubescent, longer than the calyces; calyx 4 mm. long, long-silky; lobes lanceolate, 

 acuminate, equaling the tube; corolla rose or lilac; blade of the banner suborbicular, rounded or 

 retuse at the apex, subcordate at the base, 1.5 mm. long, the claw 2-2.5 mm. long; blades of the 

 petals oblong, 2 mm. long, the claws about 0.5 mm. long; pod obliquely obovate, villous at 

 the top. 



Type locality: Hillsides near Santa Cruz, Sonora. 

 Distribution: New Mexico, Arizona, Sonora, and Chihuahua. 



22. Petalostemon confusus Rydberg, sp. nov. 



A slender annual; stem about 4 dm. high, branched above, glabrous and slightly angled; 

 leaves 1-4 cm. long, ascending; stipules subulate; leaflets 5-9, elliptic or oblong, 6-15 mm. long, 

 glabrous or sparingly pilose, dotted with scattered glands; rachis slightly margined; peduncles 

 2-5 cm. long; spikes oblong to cylindric, 1-2.5 cm. long, about 7 mm. thick; bracts lanceolate 

 to cuneate, acuminate, dark, slightly pubescent, scarious, shorter than the calyces; calyx 3-3.5 

 mm. long, densely pubescent; lobes triangular-ovate, short-acuminate, 1-1.5 mm. long; corolla 

 bluish-purple; blade of the banner oval, nearly 2 mm. long, the claw 1.5 mm. long; blades of 

 the other petals oblong, cuneate at the base, nearly 2 mm. long, the claws less than 1 mm. long; 

 pod pubescent. 



Type collected on pine plains, base of Sierra Madre, September 20, 1887, Pr ingle 1215 (U. S. 

 Nat. Herb. no. 24427, labeled Dalea polygonoides var.). 



23. Petalostemon evanescens (Brand.) Rose. 



Dalea evanescens Brand. Proc. Calif. Acad. II. 2: 146. 1889. 



A low annual; stem spreading, nearly prostrate, strigose, 6-20 cm. long; leaves 1-2 cm. 

 long, spreading; stipules subulate, 1 mm. long; rachis strigose; leaflets 7-9, cuneate-obovate, 

 retuse, 2 mm. long, strigose, minutely glandular-dotted beneath; peduncles supra-axillary, 

 1 cm. long or less; racemes 1-1.5 cm. long, lax; bracts minute, ovate-lanceolate, purplish; 



