sepals 8-14 mm. long, lacking free tips; petals pinkish or more rarely white on first 

 opening, 8-12 mm. long, red-spotted all over; capsule ovoid-pyramidal, sharply 

 4-angled, beaked, 7-8 mm. long; seeds in several rows in each locule, about 1 mm. 

 long. 



Dried up ponds and lakes in clay soil, and on muddy banks of ponds, in Okla. 

 Panhandle (Waterfall) , in the Tex. Edwards Plateau n. through the Panhandle and 

 N. M. (Union Co.), local, May-Aug.; n. on the Plains to Neb. and Wyo. 



7. Oenothera rhombipetala T. & G. 



Erect strigulose winter annual or biennial from a fleshy taproot, the stems to 1 m. 

 tall; leaves narrowly oblanceolate to narrowly ovate (broader above), 2-8 cm. long, 

 3-15 mm. wide, sinuate-pinnatifid to subentire; petioles short or absent; flowers 

 opening near sunset; mature buds erect; hypanthium 2.5-3 cm. long; sepals 1-1.8 

 cm. long, with free tips 0-1.5 mm. long; petals yellow, 1.3-2 cm. long; capsule 

 cylindric, 12-16 mm. long; seeds in 2 rows in each locule, about 1 mm. long. 



In marshes, sometimes alkaline and in sandy and waste places, in Okla. (Alfalfa 

 Co.) and in e. half of Tex., June-Sept.; Ind. to Wise, and Minn. s. to Tex. and 

 scattered (possibly introd.) e. to the Atl. Coast. 



8. Oenothera biennis L. Common evening primrose. 



Weedy variously pubescent biennial to 2 m. tall; leaves lanceolate; rosette leaves 

 sinuate-pinnatifid to denticulate, 8-30 cm. long and 1-6 cm. wide, their petioles 

 long; cauline leaves denticulate, 5-16 cm. long, 15-35 mm. wide, subsessile; flowers 

 opening near sunset; mature buds erect; hypanthium 2-5 cm. long; sepals 1-2 cm. 

 long, the free tips 1-4 mm. long; petals yellow, 1-2 cm. long; capsule thick, cylin- 

 dric, 14-25 mm. long; seeds in 2 rows in each locule, 1.2-1.8 mm. long. O. pratin- 

 cola Bartlett. 



Weedy places and woods, in wet meadows, and wet soil about ponds, lakes and 

 along streams, scattered, in Okla. (Adair and Johnston cos.) and n.e. Tex., Aug.- 

 Oct.; Alta. to Wise, and Mich., s. to Tex. and La. and e. to Atl. Coast; the species 

 as a whole ranges to Nfld., Que. and Ont. 



Represented by several varieties. . 



Var. biennis. Hairs scattered on flowers and fruits. 



Var. canescens T. & G. Hairs on flowers short and appressed. 



Var. hirsutissima Gray. Some of the hairs on floral parts long and spreading. 



9. Oneothera Hoolieri T. & G. 



Robust erect biennial or perennial to 2 m. tall; leaves oblanceolate to elliptic, 

 densely strigose and sometimes also pilose, entire to sinuate-serrulate, the rosette 

 leaves narrower near the base, 1-3 dm. long, 2-5 cm. wide, their petioles 5-18 cm. 

 long, the cauline leaves 5-15 cm. long and 8-25 mm. wide, short-petioled to sub- 

 sessile; flowers opening near sunset; mature buds erect; hypanthium 25-45 mm. 

 long; sepals 2.5-4 cm. long, with free tips 2-6 mm. long; petals yellow, fading 

 reddish, 2-4.5 cm. long; capsule thick, cylindric, 2-4 cm. long; seeds in 2 rows in 

 each locule, 1-1.6 mm. long. 



S.e. Wash, and s. Ida. to Baja Calif., Kan., Tex. and Chih. 



In our area represented by 2 subsp. as follows: 



Subsp. hirsutissima (Gray) Munz. Pubescence largely loose with some spreading 

 hairs; free sepal tips 2-4 (-5) mm. long; seeds 1.2-1.6 mm. long. Rare in wet 

 places in the Tex. Trans-Pecos and in N. M. (widespread) and Ariz. (Apache and 

 Coconino, s. to Cochise and Pima cos.), July-Oct.; Ut. and s. Colo, to w. Kan., 

 Chih. and Son. 



Subsp. Hewettii Cockll. Pubescence appressed; free sepal tips 3-6 mm. long; 

 seeds about 1 mm. long. Incl. var. irhgua (Woot. & Standi.) Gates, O. Simsiana 

 sensu Munz, Fl. Tex. 226. 1944. Rare in wet places in the Tex. Trans-Pecos and in 



1198 



