618 FABACEAE 



subulate-lanceolate, mostly longer than the tube : corolla purplish, 5-6 mm. long : pods 

 linear, about 2 cm. long, slightly curved, short-beaked. [Astragalus Nuttallianus DC.] 

 In dry soil, Arkansas and Texas to Arizona. Spring. 



4. Hamosa macile'nta Small. Plant somewhat strigillose. Stems tufted, 1-1.5 dm. 

 long, ascending : leaves 2.5-4.5 cm. long ; leaflets 7-9, the blades linear, 9-12 mm. long, 

 acute, sessile or essentially so : peduncles surpassing the accompanying leaves : calyx 

 sparingly pubescent ; lobes subulate, the lower ones longer than the tube : corolla purplish, 

 nearly 1 cm. long: pods linear, 2-2.5 cm. long, glabrous. 



On hillsides and prairies, near the Blanco, Texas. Summer. 



5. Hamosa austrina Small. Plant copiously strigillose. Stems branched at the 

 base, the branches ascending or decumbent, 1-4 dm. long, mostly simple : leaves numerous, 

 1.5-5 cm. long ; leaflets mostly 9-11, the blades oblong to oval, 2-6 mm. long, acute or 

 blunt : racemes head-like, on slender peduncles 1-4 cm. long : calyx 4 mm. long, very 

 short-pedicelled ; tube densely pubescent ; lobes subulate-lanceolate, longer than the tube : 

 corolla purplish, 5-6 mm. long : pods linear, 1.5-2 cm. long, strongly curved at the base, 

 finely pubescent and very delicately reticulated. 



On plains and prairies, Texas to California and Mexico. Spring. 



23. HOLCOPHACOS Kydb. 



Perennial low spreading herbs. Leaves alternate, the stipules nearly free and distinct : 

 leaflets numerous, the blades entire, mostly truncate or notched at the apex. Flowers 

 perfect, few in short racemes. Calyx short-campanulate : lobes short, relatively broad. 

 Corolla pink or purplish : standard with a broad deeply notched blade : wings slightly 

 longer than the keel-petals. Stamens 10 : filaments diadelphous : anthers alike. Ovary 

 sessile. Ovules many. Pod linear or oblong, leathery, deeply sulcate along both sutures, 

 but 1 -celled, without even a partial partition. Seeds numerous. 



Calyx-lobes triangular : pods about twice as long as broad. 1. H. Engelmannii. 



Calyx-lobes lanceolate : pods 3-4 times as long as broad. 2. H. distortus. 



1. Holcophacos Engelmannii (Sheldon) Kydb. Plant nearly glabrous. Stems 

 branching at the base, the branches diffuse or procumbent, 8-35 cm. long, simple or branch- 

 ing : leaves 3-15 cm. long ; leaflets 15-25, the blades oblong to obovate, 3-7 mm. long, 

 rounded or notched at the apex, short-stalked : peduncles surpassing the subtending leaves : 

 racemes ovoid or oblong : calyx strigillose ; lobes triangular, shorter than the tube, more or 

 less spreading : corolla purplish, about 1cm. long: pods 1-celled, glabrous, 1-1.8 cm. long, 

 about twice as long as broad. [Astragalus Engelmannii Sheldon.] 



In dry soil, Texas. Spring and summer. 



2. Holcophacos distdrtus (T. & G. ) Kydb. Plant glabrous or sparingly pubescent. 

 Stems branched at the base, the branches ascending or prostrate, 1-4 dm. long : leaves 3-8 

 cm. long ; leaflets 17-23, the blades oval, obovate or cuneate, 3-10 mm. long, rounded or 

 notched at the apex, short-stalked : peduncles about as long as the subtending leaves or 

 longer : racemes ovoid or cylindric : calyx minutely pubescent ; lobes lanceolate, shorter 

 than the tube, erect : corolla purplish blue, 8-10 mm. long : pods crescent-shaped, 2-2.5 

 cm. long, 3 to 4 times as long as broad, short-beaked. [Astragalus distortus i . & G-.] 



In dry soil, Iowa to West Virginia, Mississippi and Texas. Spring and summer. 



24. TIUM Medic. 



Perennial caulescent herbs, various in habit. Leaves alternate, the stipules nearly 

 free and distinct : leaflets numerous, the blades entire. Flowers perfect, in short or 

 elongated racemes. Calyx mostly campanulate : lobes nearly equal, sometimes relatively 

 long. Corolla purple or ochroleucous, or white : standard with a relatively broad, some- 

 times notched, blade. Stamens 10 : filaments diadelphous : anthers alike. Ovary more 

 or less distinctly stipitate. Ovules numerous. Pod narrow, more or less tapering at both 

 ends, usually stipitate, membranous or rather firm, 1-celled, obcordate or triangular in 

 cross-section, the ventral suture strongly sulcate and rarely with a narrow partial partition. 



Pods densely pubescent. 1. T. intonsum. 

 Pods glabrous. 



Leaflets with obcordate blades : corolla less than 10 mm. long : pods reticulated. 2. T. obcordatum. 



Leaflets with linear blades : corolla over 10 mm. long : pods not reticulated. 3. 1. apilosum. 



