Genus 7. 



EVENING-PRIMROSE FAMILY. 



595 



2. Oenothera biennis L. 



Common Evening-Primrose. 

 Fig. 3038. 



Night Willow-herb. 



Oenothera biennis L, Sp. PI. 346. 1753. 



Erect, generally stout, biennial, simple 

 and wand-like or branched, i°-6° high, 

 more or less hirsute-pubescent, rarely gla- 

 brate. Leaves lanceolate to ovate-lanceo- 

 late, acute or acuminate, narrowed and 

 sessile at the base or the lowest petioled, 

 repand-denticulate, i'-6' long; flowers open- 

 ing in the evening, i'-2i' broad ; calyx-tube 

 slender, much longer than the ovary, the 

 lobes linear, contiguous at the base, re- 

 flexed; capsules oblong, narrowed above, 

 erect, pubescent, i'-li' long, 2j"-3" thick, 

 nearly terete, longer than the deciduous 

 upper bracts. 



Usually in dry soil, Labrador to Florida, 

 Minnesota, Arkansas and Texas. Large ram- 

 pion.. Tree-primrose. Four-o-clock. Coffee- or 

 fever-plant. King's-cure-all. Scurvish or scab- 

 ish. June-Oct. 



Oenothera grandiflora Ait., of the Gulf 

 States, is taller and has much larger flowers', 

 up to 4' broad. Large-flowered races of the 

 preceding species have been mistaken for it. 



Oenothera Lamarckiana Ser., a large-flowered plant, in some features intermediate between 

 0. biennis and O. grandiflora, not definitely known in the wild state, but frequently cultivated, 

 apparently originated in Old World gardens over one hundred years ago. 



Oenothera muricata L. Northern Evening-Primrose. Fig. 3039. 



Oenothera muricata L. Syst. Ed. 12, 263. 1767- 



Similar to the preceding species, usually simple, 

 3° high or less, the stem puberulent and with 

 longer hairs enlarged at the base. Leaves lanceo- 

 late, mostly narrower than those of 0. biennis, 

 entire, or slightly repand-denticulate ; flowers 

 i'-2' broad; capsules hirsute, narrowly oblong- 

 cylindric, about i' long, shorter than the per- 

 sistent bracts. 



Sandy and gravelly soil, Newfoundland to south- 

 eastern New York and New Jersey. July-Sept. 



