FABACEAE 621 



phous : anthers alike or nearly so. Ovary sessile or short-stalked. Style filiform or 

 dilated at the base. Ovules solitary or rarely 2 in a cavity. Pod broad, indehiscent. 



Leaf-blades palmately 3-5-foliolate or rarely 7-foliolate. 

 Plants tall, with erect or ascending stems or branches. 

 Corolla 4-8 mm. long. 



Pods lunate, with wrinkled sides. 1. P. Lupinellus. 



Pods ovoid or ovate. 



Pod abruptly narrowed into a short beak. 2. P. floribunda. 



Pod gradually narrowed into a slender elongated beak. 



Leaflets mostly 3 : calyx filiform-pediceled, finely pubescent. 3. P. linearifolia. 



Leaflets mostly 5 : calyx sessile or nearly so, densely silky. 4. P. digitata. 



Corolla 10-20 mm. long. 



Bract fully as long as the calyx. 



Leaflets broadest at the middle : corollas about 1 cm. long. 5. P. Reverchonii. 



Leaflets broadest above the middle : corollas 1.5-2 cm. long. 6. P. cuspidata. 



Bract about as long as the pedicel or shorter. 



Leaflets linear, many times longer than broad : stems simple or nearly so. 7. P. cyphocalyx. 

 Leaflets broadest above the middle, barely twice as long as broad : stems 



widely branched. 8. P. canescens. 



Plants low, acaulescent or acaulescent-like, with spreading stems or branches. 



Petioles strigose. 9. P. hypogaea. 



Petioles hirsute. 



Leaflets glabrous except the margins and midnerve : calyx-lobes about as 



broad as long. 10. P. subacaulis. 



Leaflets pubescent : calyx-lobes elongated. 11. P. esculenta. 



Leaflets pinnately 3-foliolate or rarely 1-foliolate. 

 Racemes short, subglobose to oblong. 

 Corolla 5-7 mm. long. 



Pods suborbicular, reticulated. 12. P. virgata. 



Pods ovoid, not reticulated. 



Stems or branches trailing : leaflets with entire blades. 13. P. rhombifolia. 



Stems or branches erect : leaflets with toothed blades. 14. P. Americana. 



Corolla 10-20 mm. long. 15. P. simplex. 



Racemes elongated, cylindric. 



Leaflets less than 2 cm. broad : pods suborbicular, about 5 mm. long. 



Upper calyx-lobes triangular or triangular-ovate. 16. P. gracilis. 



Upper calyx-lobes lanceolate. 17. P. pedunculata. 



Leaflets over 2 cm. broad : pods ovate, about 10 mm. long. 



Blades of the leaflets with rounded bases : standard with a blade 2-3 mm. 



wide. 18. P. Onobrychis. 



Blades of the leaflets with cordate bases : standard with a blade 7-8 mm. 



broad. 19. P. macrophylla. 



1. Psoralea Impine'llus Michx. Foliage glabrous, somewhat glandular. Stems 

 erect or nearly so, 2-6 dm. tall, often branched throughout : stipules setaceous : petioles 

 usually shorter than the leaflets : leaflets 5-7, the blades linear-filiform, or those on the 

 lower part of the stem narrowly linear, 3-8 cm. long : peduncles surpassing the subtend- 

 ing bracts : racemes shorter than the peduncles : calyx campanulate ; lobes triangular to 

 triangular-lanceolate, the shorter ones nearly as long as the tube : corolla blue or violet, 

 4-6 mm. long : pods lunate, about 1 cm. long, tAvisted, longitudinally wrinkled, with a 

 curved beak. 



In sandy pine lands, Xorth Carolina to Florida. Spring and summer. 



2. Psoralea floribunda Nutt. Foliage canescent. Stems erect, 3-12 dm. tall, pro- 

 fusely branched: stipules subulate: petioles shorter than the leaflets: leaflets 3-7, the 

 blades oblong-linear or oblong-oblanceolate, 1-3.5 cm. long, glandular: peduncles sur- 

 passing the subtending bracts : racemes commonly about as long as the peduncles : calyx 

 campanulate ; lobes triangular, except the lower one, shorter than the tube : corolla bluish 

 purple, 4-5 mm. long : pods ovoid, 6-8 mm. long, glandular, with stout straight beak. 



On prairies, Illinois to Montana, Texas, Arizona and Mexico. Spring to fall. 



3. Psoralea linearifolia T. & G. Foliage strigillose or glabrate in age, more or less 

 glandular. Stems erect, 2-6 dm. tall, widely branched : stipules setaceous to narrowly 

 lanceolate : leaflets 1-3, the blades linear, 2-6 cm. long, wrinkled : peduncles much longer 

 than the subtending bracts : racemes as long as the peduncles or shorter : calyx slightly 

 pubescent ; tube campanulate ; lobes ovate or oblong-ovate, about as long as the tube : 

 corolla blue, 7-8 mm. long : pods oblong-ovoid, 8 mm. long, glandular, with a straight 

 short beak. 



On prairies, Nebraska to Texas. Spring and summer. 



4. Psoralea digitata Nutt. Foliage pubescent with appressed hairs. Stems erect, 

 2-6 dm. tall, branched : stipules lanceolate : leaflets 3-5, the blades linear to narrowly ob- 

 lanceolate, 2-3.5 cm. long, acute, somewhat glandular: peduncles elongated, longer than 

 the racemes : calyx silky, accrescent ; tube turbinate-campanulate ; lobes acuminate, the 

 lower one longer than the tube : corolla 7-8 mm. long ; pods obliquely oval, included in 

 the calyx, minutely pubescent, the body 5-6 mm. long, the beak 4-5 mm. long. 



In sandy soil and on prairies, South Dakota to Texas. Spring and summer. 



