842 EPILOBIACEAE 



over 4 cm. wide : capsules mostly over 2 cm. long. 

 Plants glabrous or minutely pubescent : leaf-blades mainly of 



a linear or narrowlv oblong type. 7. K. riparia. 



Plants hirsute : leaf-blades of an elliptic or elliptic-lanceolate 



type. ' 8. A', pratensis. 



b. Petals less than 13 mm long : capsules glabrous or nearly so. 9. K. pumila. 



B. Capsules oblong or nearly so, sometimes abruptly narrowed into a short pedi- 

 cel-like base. 

 Capsule-body less than 1 cm. long : plants not glaucous. 10. K. fruticosa. 



Capsule-body over 1 cm. long: plants glaucous. 11. K. glauca. 



1. KneifBa linifolia (Nutt. ) Spach. Stems slender, 1.5-4.5 dm. tall, finely pubescent 

 above : basal leaves tufted, with oblanceolate or spatulate blades about 2-5 cm. long ; 

 stem-leaves filiform-linear, entire, 1-3 cm. long : flowers in loose spike-like racemes : sepals 

 2-3.5 mm. long: corolla 6-8 mm. broad: stigma-lobes very short: capsule-body ovoid, 

 4-6 mm. long, puberulent, sharply 4-angled or slightly winged. \_Oenothera linifolia Nutt.] 



In dry soil, Illinois to Kansas, Georgia, Louisiana and Texas. Spring and summer. 



2. KneifEa arenlcola Small. Stems erect, 1.5-4.5 dm. tall, branched above, strigil- 

 lose : leaf-blades linear or nearly so, or some of them narrowly oblong, 1.5-5 cm. long, 

 rather obtuse, silvery strigose, thick, often revolute, entire or essentially so : hypanthium 

 somewhat hirsute : sepals 5.5-8 mm. long : petals 16-23 ram. long : capsnle-body globular 

 or obovoid-globose, about 4 mm. long, more or less hirsute, broadly winged above, nar- 

 rowed into a relatively stout hairy pedicel-like base. 



On sand hills or in pine lands. North Carolina to Georgia and Alabama. Sunmer and fall. 



3. KneifBa subglobosa Small. Stems slender, 2-3 dm. tall, much branched, puberu- 

 lent, widely stoloniferous, red : basal leaves 4-10 cm. long, with spatulate undulately 

 toothed blades, each gradually narrowed into a short petiole-like base : stem-leaves often 

 numerous ; blades linear or nearly so, 2-7 cm. long, entire or distantly toothed : hypan- 

 thium villous or silky : sepals 6-9.5 mm. long : petals 1.5 to almost 2 cm. long : capsule- 

 body globose-obovoid, 6-7 mm. long, terminating a much longer pedicel-like base, the angles 

 strongly winged, the faces strongly ridged. 



In sandy soil, North Carolina to Georgia and Alabama. Summer and fall. 



4. Kneiffia longipedicellita Small. (Stems slender, puberulent, erect or assurgent, 

 3-8.5 dm. tall : basal leaves with spatulate or obovate-spatulate blades 3.5-7.5 cm. long: 

 stem-leaves few; blades linear-lanceolate, 2.5-6.5 cm. long, entire, sometimes undulate: 

 sepals hirsute, 12-19 mm. long : petals mostly over 2 cm. long : capsule-body narrowly ob- 

 ovoid, 6-10 mm. long, terminating a much longer pedicel, the angles with stout closely 

 pubescent wings, the faces strongly ridged. 



In dry soil, New York to West Virginia, Florida and Alabama. Spring and summer. 



5. KneifSa Ifneaiis (Michx. ) Spach. Stems slender, pilose or nearly glabrous, erect 

 or ascending, 1.5-5 dm. tall, finally angled : basal leaves with spatulate or broadly oblance- 

 olate blades, 5-8 cm. long, entire or nearly so : stem-leaves usually few ; blades linear or 

 linear-lanceolate, 2.5-7.5 cm. long, slightly toothed : sepals about 1 cm. long, pubesceiit : 

 petals mostly 1.5-2 cm. long : capsule-body oblong-clavate, 7-14 mm. long, the angles with 

 papery glabrous or loosely pubescent wings, its faces ridged. [Oenothera linearis Michx.] 



In dry or sandy soil, Connecticut to Arkansas and Georgia. Spring to fall. 



6. Kneiffia Spachi^na (T. & G. ) Small. Stems minutely puberulent and somewhat 

 hoary, erect, 1-1 dm. tall, terete, branched at the base or above : basal leaves spatulate or 

 oblong-spatulate : stem-leaves few ; blades linear, 2-6 cm. long, nearly flat, obtuse or acute, 

 undulate, slender-petioled : sepals about 10 mm. long, minutely pubescent : petals broad, 

 9-15 mm. long: capsule-body club-shaped, 1-1.5 cm. long, 4-winged, essentially sessile. 

 [ Oenothera Spaehiana T. & G. ] 



In sandy soil, Texas and Louisiana. Spring and summer. 



7. Kneiffia riparia (Nutt.) Small. Stems stout, finely pubescent, 5-12 dm. tall, often 

 sparingly branched : basal leaves with spatulate blades commonly over 10 cm. long : stem- 

 leaves often numerous ; blades linear to linear-lanceoLtte, 5-13 cm. long, or shorter on 

 branches, acute or acutish, entire or undulate-denticulate : sepals about 2 cm. long, finely 

 pubescent : petals over 2 cm. long : capsule-body clavate, pubescent all over, mostly over 2 

 cm. long. [Oenothera riparia Nutt.] 



On river banks or low grounds. North Carolina to Georgia. Spring and summer. 



8. Kneiffia prat6nsis Small. Stems erect or nearly so, 5-11 dm. tall, often sparingly 

 branched above, hirsute : leaf-blades narrowly elliptic to elliptic-lanceolate, 3-11 cm. 

 long, undulate or sinuate, acute, thin, hirsute, flat : hypanthium more or less hirsute : 

 sepals 17-22 mm. long, the free tips 2.5-4 mm. long : petals 2-3.5 cm. long : capsule-body 

 clavate, 17-21 mm. long, narrowly winged, hirsute, the pedicel-like base usually very short. 



In low grounds, Ohio to Missouri and Arkansas. Summer and fall. 



