EVENING-PRIMROSE FAMILY 593 



9. PHAEOSTOMA Spach. 



Annual caulescent herbs. Leaves alternate, narrow. Flowers in terminal 

 racemes. Hypanthium-tube above the ovary obconic. Sepals 4, reflexed. 

 Petals 4, rhomboidal, with a broad short blade, entire, purple. Stamens 8, all 

 perfect, with hairj' scales at the bases. Stigma with broad lobes. Capsule 

 elongate, somewhat fusiform, 4-angled, 4-cellcd, 4-valved to the middle. Seeds 

 without a coma, obliciuely prismatic. 



1. P. rhomboidea (Dougl.) A. Nels. Stem puberulent or glabroiis, 3-6 

 dm. high; leaves petioled; blades oblong-lanceolate or oblong-ovate, 3-5 cm. 

 long; petals purple, 5-7 mm. long, short-clawed, the claw often with a tooth on 

 each side; blades rhombic, entire; capsule 15-25 mm. long, 4-angled, nearly 

 glabrous. Clnrkia rhntnboidcaDoup.. Ospiariihes gauroides (Don.) h]\]a. Sandy 

 soil and hillsides; B.C. — Mont. — Utah — Calif. Submont. Ap-Jl. 



10. OENOTHERA L. Evening-primrose. 



Biennial or annual stout herbs, with taproots. Leaves alternate, undulate 

 or toothed. Flowers in terminal spikes, nocturnal, from erect buds. Hypan- 

 thium-tube above the ovary funnelform. Sepals 4, reflexed. Petals 4, usually 

 obcordate, j'ellow, or in age turning purplish. Stigmas with 4 linear lobes. 

 Stamens 8. Capsule usually tapering uj^wards, 4-celled, loculicidal, 4-valved. 

 Seeds in two or more rows, horizontal. [Onagra Adans.] 



Free tube of the hypantliium 1..5— 4 cm. long. 



Petals turning pink or purplish in age, 3—4 cm. long. 



Free tips of the sepals about 4 mm. long; pube.scence of the leaves short, that of 



the caly.x not very copious. 1. O. Hookeri. 



Free tips of the sepals 2-2. .5 mm. long; pubescence of the leaves long and loose, 

 that of the calyx copious. 2. O. hirsutissima. 



Petals not tiu-ning pink or purplish in age, less than 3 cm. long. 

 Free tips of the sepals 3 mm. long or longer. 



Spike not conspicuously leafy-bracted; bracts lance-linear, none except the 

 very lowest ones exceeding the hj-panthium-tube or the fruit in length. 



3. O. suhulifera. 

 Spike conspicuously leafy-bracted; bracts, even the upper ones, exceeding the 

 hypanthium-tube or the friiit in length. 

 Bracts caudate-acuminate, with twisted tips; plant canescent; corolla 



about 15 mm. long. 4. O. Cockerellii. 



Bracts not caudate-acuminate. 



Petals 10-12 mm. long; plant green. 5. O. muricata. 



Petals 20-30 ram. long; plant cane.scent. 6. O. ornata. 



Free tips of the sepals about 2 nun. long. 



Stem erect; petals 12-20 mm. long. 7. O. strigosa. 



Stem decumbent; petals about 10 mm. long. 8. O. depressa. 



Free tube of the hypantliitun 8-15 cm. long. 



Leaves linear, entire. 9. o. longissima. 



Leaves ovate or lanceolate, sinuate-dentate. 10. O. Jamesii. 



1. O. Hookeri T. & G. Biennial, with a taproot; stem 5-10 dm. high, 

 erect, angled, more or less hirsute and canescent; leaves lanceolate, repand-den- 

 tate, hirsute and canescent, 5-20 cm. long; free tube of the hypanthiimi 3.5-4 

 cm. long; sepals about 3 cm. long, more or less hirsute; petals 3-4 cm. long; 

 capsules 4^5 cm. long, hirsute and more or less canescent. Onagra Macbridei 

 A. Nels. VaUeys: Mont.— N.M.— Calif.— B.C.; nMex. SubmonL—Mont. Je-S. 



2. O. hirsutissima (A. Gray) Rydb. Biennial, with a taproot; stem 3-6 

 dm. high, grayish pubescent, as well as coarsely hirsute, sometimes aknost his- 

 pid; leaves lanceolate or linear-lanceolate, entire, or merely denticulate, 5-10 

 cm. long, densely hirsute; bracts Unear-lanceolate, shorter than the hypanthium- 

 tube; free part of the hjiianthimn about 3 cm. long; sepals about 3 cm. long; 

 petals 3-4 cm. long; capsule 2.5-3 cm. long. Oenothera biennis hirsutissima A. 

 Gray. Valleys: X.M.— Colo.— Ariz.— Chihuahua. Jl-S. 



3. O. subulifera Rydb. Biennial; stem 3-6 dm. high, sparingly hirsute; 

 leaves lanceolate or the lower oblanceolate, densely pubescent, somewhat ciner- 

 eous, 5-15 cm. long, minutely denticulate; free tube of the hypanthiiun 1.5-2.5 

 cm. long; calyx-lobes about 2 cm. long, sparingly hirsute, somewhat glandular; 

 free tips 3-4 mm. long, slender; petals 1.5-2 cm. long; capsule 2.5-3.5 cm. 



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