456 NORTH AMERICAN FLORA [Volume 24 



ciliate; leaflets 13-15, obovate or obcordate, 4-8 mm. long, petiolulate, truncate or notched at 

 the apex, glabrous above, pilose beneath; j>eduncles 3-6 cm. long; racemes dense, about 1 cm. 

 long; bracts lanceolate, about 0.5 mm. long; pedicels less than 1 mm. long; calyx sparingly 

 pilose, the tube campanulate, 1 mm. long, the teeth subulate, fully 1 mm. long; corolla 5-6 

 mm. long; banner purplish, with an ochroleucous spot and dark-purple veins; wings shorter, 

 ochroleucous, the blade obliquely oblong, rounded at the apex and with a reflexed auricle; 

 keel-petals dark-purple, fully as long, the blade lunate, with an acute auricle and acutish tip; 

 pod glabrous, coriaceous, cross-veined, 6-7 mm. long, 2 mm. wide, and 4 mm. thick, the 

 lateral view obliquely lanceolate, with the upper suture straight, the dorso-ventral view ovate, 

 the cross-section broadly cordate; seeds mostly 2 in each cell, obliquely reniform. 



Type locality: Texas. 



Distribution: Texas. 



Illustration: M. E. Jones, Rev. Astrag. pi. 71, f. 266. 



2. Hesperastragalus oxyrhynchus (Hemsl.) Rydb. Bull. Torrey 



Club 53: 165. 1926. 



Astragalus oxyrhynchus Hemsl. Biol. Centr. Am. Bot. 1: 265. 1880. 

 Tragacantha oxyrhyncha Kuntze, Rev. Gen. 947. 1891. 

 Astragalus angelinus M. E. Jones, Rev. Astrag. 286. 1923. 



A perennial, with several slender under-ground stems; stems decumbent, 1-2 dm. long, 

 strigulose, often canescerft; leaves 3-6 cm. long, ascending, the rachis strigulose; stipules 

 deltoid, strigose, 3 mm. long; leaflets 15-25, linear, retuse to obtuse at the apex, glabrous above, 

 strigose beneath; peduncles 3-7 cm. long, erect; racemes dense, 2-4 cm. long, many-flowered; 

 bracts lanceolate, 1 mm. long; pedicels reflexed, 2 mm. long; calyx strigose with mixed white 

 and black hairs, the tube campanulate, 1 .5 mm. long, the teeth subulate, about as long ; corolla 

 5-6 mm. long; banner broadly obovate, abruptly arched, slightly retuse, purplish with dark 

 veins; wings slightly shorter, the blade obliquely oblong, falcate; keel-petals nearly as 

 long, the blade semi-orbicular, obtuse; pod strigose, cross-reticulate, coriaceous, 7 mm. long, 

 3 mm. wide, and 4 mm. thick, the lateral view semi-ovate, straight on the upper suture, the 

 dorsi-ventral view ovate, the cross-section broadly cordate, but only slightly sulcate on the 

 lower suture. 



Type locality: Tizapan, Valley of Mexico (Federal District). 



Distribution: Mexico and Hidalgo. 



Illustrations: M. E. Jones, Rev. Astrag. pi. TO, f. 261 (poor); pi. 71, f. 272. 



3. Hesperastragalus diphacus (S. Wats.) Rydb. Bull. Torrey 



Club 53: 166. 1926. 



Astragalus diphacus S. Wats. Proc Am. Acad. 17: 342. 1882. 



An annual or perennial, with a taproot; stems branched at the base, usually decumbent, 

 1-3 dm. long, strigose, striate; leaves 5-10 cm. long, ascending, the rachis strigose; stipules 

 lanceolate, 4-6 mm. long, strigose; leaflets 13-25, linear, petioluled, obtuse, glabrous above, 

 strigose beneath; peduncles 5-15 cm. long; racemes dense and short, 2-4 cm. long; bracts 

 lance-subulate, 2-3 mm. long, black-hairy; pedicels about 1 mm. long, reflexed; calyx black- 

 hairy, the tube campanulate, 3 mm. long, the teeth subulate, nearly as long; corolla whitish, 

 about S mm. long; banner obovate, retuse, abruptly arched at the middle; wings shorter, the 

 blade obliquely oblong, falcate, with a large basal auricle; keel petals shorter, the blade semi- 

 orbicular, rounded at the apex, subcordate at the base; pod strigose, 7-S mm. long, 4 mm. wide, 

 and 7 mm. thick, cross-reticulate, rounded and mucronate at the tip, sulcate on both sutures; 

 seeds 2 or 3 in each cell. 



Type locality: San Miguelito Mountains, San Luis Potosi. 

 Distribution: San Luis Potosi and Zacatacas. 

 Illustration: M. E. Jones. Rev. Astrag. pi. 71, f. 27 1. 



