FABACEAE 653 



form. Style bearded. Stigma oblique or lateral. Pod slightly flattened, straight or 

 curved. Seeds with rounded ends. WILD BEAN. BEAN- VINE. 



Stems trailing : leaflets mostly broader than long. 1. P. sinuatus. 

 Stems climbing ; leaflets mostly longer than broad. 



Blade of the terminal leaflet not hastate. 2. P. polystachyus. 



Blade of the terminal leaflet hastate. 3. P. smiladfolius. 



1. Fhaseolus sinuatus Nutt. Foliage glabrous or nearly so. Stems trailing, 1-4 

 m. long, branching : leaflets 3, the blades deltoid-ovate in outline with 3 more or less 

 prominent lobes, 2-4 cm. long, reticulated, mucronulate, truncate or very broadly cuneate 

 at the base : racemes several times longer than the subtending leaves, simple ; rachis wire- 

 like : pedicels 5-10 mm. long : calyx campanulate, 2.5-3 mm. long ; lobes rounded or 

 apiculate : corolla pale purple ; standard with a blade nearly 1 cm. wide : pods somewhat 

 scimitar-shaped, 3.5-4 cm. long. 



In dry pine lands or hammocks, Florida to Mississippi. Summer. 



2. Fhaseolus polystachyus ( L. ) B. S. P. Foliage minutely pubescent. Stems climb- 

 ing, 1-4 m. long, branching : leaflets 3, the blades ovate to orbicular-ovate, 4-10 cm. long, 

 acuminate, often conspicuously nerved, rounded or subcordate at the base : racemes or 

 panicles slender, surpassing the subtending leaves, simple or compound, short-peduncled : 

 pedicels 4-8 mm. long : calyx campanulate, 2.5-3 mm. long ; lobes rounded or somewhat 

 triangular : corolla purple or whitish : pods scimitar-shaped, 4-8 cm. long, often glaucous. 

 [P. perennis Walt.] 



In thickets, Canada to Minnesota, Florida, Louisiana and Nebraska. Summer. 



3. Fhaseolus smilacifolius Pollard. Foliage minutely pubescent. Stems twining, 

 1-4 m. long, branching : leaflets 3, the blades very thin, ovate in outline, 4-8 cm. long, 

 acute, more or less distinctly 3-lobed, soon glabrous : racemes usually shorter than the sub- 

 tending leaves : pedicels slender, 5-15 mm. long : calyx glabrous, campanulate, 2.5-3 mm. 

 long ; lobes rounded : corolla pink or white ; keel-petals 1 cm. long ; standard with a 

 broad blade nearly 1 cm. long : pods 5-6 cm. long. 



In hammocks, Florida. Summer and fall. 



51. STROPHOSTYLES Ell. 



Annual or perennial herbaceous vines, with trailing or twining stems. Leaves alter- 

 nate : blades pinnately 3-foliolate, stipulate : leaflets with thickish, entire or lobed 

 blades. Flowers perfect, in clusters terminating long axillary peduncles. Calyx sessile 

 or short-pedicelled : lobes 5, equal or the upper 2 more or less united. Corolla white or 

 pink-purple : standard with a blade about as broad as long : wings broadened upward : 

 keel-petals curved. Stamens 10, diadelphous (9 and 1). Anthers similar. Style bent, 

 bearded, persistent. Pod narrow, somewhat flattened, straight or nearly so. Seeds truncate, 

 smooth or granular. WILD BEAN. 



Perennial. 1. S. umbellata. 



Annual. 



Leaflets fully thrice as long as broad. 2. S. pauciflora. 



Leaflets less than twice as long as broad. 



Stems 1-2 m. long, trailing or low-twining : leaflets, or some of them, with lobed 



blades. 3. S. helvola. 



Stems 3-9 m. long, high-climbing : leaflets with entire blades. 4. S. Missouriensis. 



1. Strophostyles umbellata (Muhl. ) Britton. Perennial, more or less pubescent. 

 Stems trailing, 3-15 dm. long, branching : leaflets 3, the blades oblong-lanceolate, varying 

 to ovate or lanceolate, 1-4 cm. long, obtuse or acute, sometimes slightly lobed : peduncle 

 3-6 times longer than the subtending leaf-like bracts : pedicels very short : calyx broadly 

 campanulate, 2.5-3 mm. long, the lower lobe acute, somewhat shorter than the tube : co- 

 rolla pink or pale purple, often fading yellowish ; standard with a blade 1-2 cm. broad : 

 pods linear, slightly flattened, 2.5-5 cm. long, straight. 



In dry sandy soil, New York to Missouri, Florida and Louisiana. Summer and fall. 



2. Strophostyles pauciflora (Benth. ) S. Wats. Annual, minutely pubescent. 

 Stems trailing or climbing, 3-9 dm. long, branching : leaflets 3, the blades linear to lanceo- 

 late, 1.5-3.5 cm. long, apiculate at the apex, scarcely ever lobed, short-stalked : peduncles 

 surpassing the subtending leaves : pedicels very short : calyx hirsute, about 1.5 mm. long, 

 the lower lobes slender, about as long as the tube : corolla pale purple ; standard with a 

 blade less than 1 cm. broad : pods linear, flattish, 2-3 cm. long, strigose. 



On river banks, Minnesota to Indiana, Nebraska, Louisiana and Texas. Summer and fall. 



3. Strophostyles helvola (L. ) Ell. Annual, often villous-hirsute. Stems often 

 branching at the base ; branches trailing, 3-12 dm. long, widely branching : leaflets 3, the 



