Genus io. 



EVENING-PRIMROSE FAMILY. 



6oi 



Fig. 3052. 



4. Kneiffia linearis (Michx.) Spach. Narrow-leaved Sundrops. 



Oenothera linearis Michx. Fl. Bor. Am i : 225. 1803. 

 Kneiffia linearis Spach, Hist. Veg. 4: 376. 1835. 



Biennial or perennial, slender, puberulent, 

 loosely pilose, or nearly glabrous. Stems erect 

 or ascending, 6'-2o' tall, simple or much-branched 

 above, finally angled ; basal leaves spatulate or 

 broadly oblanceolate, 2'-^,' long, entire or nearly 

 so; cauline leaves linear, or linear-lanceolate, i'-3' 

 long, slightly toothed, acute or obtuse, short- 

 petioled; flowers yellow, i'-i¥ broad; racemes 

 i'-4' long; calyx slightly pubescent, its tube 4"-6" 

 long, its segments linear-lanceolate, longer than 

 the tube ; petals obovate, shallowly notched at the 

 apex and eroded ; capsule oblong club-shaped, 

 4"-7" long, the angles with papery glabrous wings, 

 its faces ridged, narrowed into pedicels which are 

 much shorter than the bodies ; seeds irregular, ¥' 

 long, angled. 



In dry soil, Connecticut to Tennessee and Georgia. 

 June-Sept. 



Kneiffia riparia (Nutt.) Small is pubescent, has 

 larger flowers, the fruit very much like that of K. 

 linearis: it ranges from eastern Long Island to Geor- 

 gia, near the coast. 



5. Kneiffia pratensis Small. Meadow Sundrops. 

 Fig. 3053. 



K. pratensis Small, Fl. SE. U S. 842. 1903. 



Oenothera pratensis Robinson, Rhodora 10: 34. 1908. 



Erect or nearly so, perennial, ii°-32° high, often 

 branched above, hirsute with spreading hairs. Leaves 

 oblone-lanceolate or elliptic-lanceolate, 4J' long or less, 

 5"-io ' wide, the margins sinuate or entire, the apex acute, 

 or that of the lower leaves obtuse; flowers leafy-bracted, 

 i4'-2j' broad; tube of the calyx somewhat hirsute, the 

 lobes with narrow hirsute tips; capsule clavate, sessile, 

 about 10" long, hispid. 



Low grounds. Ohio to Iowa, Missouri and Arkansas, 

 corded from eastern New England. June-Aug. 



Re- 



6. Kneiffia pumila (L.) Spach. Small Sun- 

 drops. Fig. 3054. 



Oenothera pumila L. Sp. PI. Ed. 2, 493. 1762, 

 Oenothera chrysantha Michx. Fl Bor. Am. i : 225. 1S03 

 Kneiffia pumila Spach, Hist. Veg. 4: 377. 1835. 



Erect, branched or simple, finely puberulent, 8'-2° 

 high. Leaves oblanceolate or oblong, obtuse or obtusish 

 at the apex, narrowed at the base and often petioled, 

 entire or very nearly so, i'-2' long, 2"-4''' wide, usually 

 glabrous; the basal ones broader and shorter; flowers 

 in terminal, leafy-bracted spikes, yellow, diurnal, 4"-i2" 

 broad ; calyx-tube shorter than the ovary, the lobes 

 linear-lanceolate, reflexed ; petals obcordate ; capsule 

 sessile or short-stalked, glabrous, club-shaped, 3"-6" 

 long, the body obovoid, somewhat wing-angled. 



In dry soil, Newfoundland to Manitoba, south to New 

 Jersey, Georgia and Wisconsin ; apparently erroneously re- 

 corded from Kansas. Ascends to 2200 ft. in Virginia. 

 June-Aug. 



