EVENING-PRIMROSE FAMILY 603 



Petals 4-6 mm. long; leaves and stem sparingly hairy or glabrate. 



Leaves interruptedly pinnate, the larger alternate pairs 12 or more, not deduced 



10. C. multijuga. 



1. C. pterosperma (S. Wats.) SmaU. Stem slender, 5-10 cm. high, branched, 

 hirsute; leaves oblong-lanceolate, 1-2 cm. long, entire, hispidulous; tube of 

 hypanthium 1 mm. long; petals obcordate, rose-colored, 1.5-2 mm. long; capsule 

 cyhndric-clavate, 12-18 mm. long; seeds 2 mm. long, the margins thin, incurved, 

 cellular ly tuber culate. Oenothera pterosperma S. Wats. Foot-hills: Utah Calif 

 Son. My-Je. 



2. C. scapoidea Nutt. Stem glabrous, 1-3 dm. high, simple or branched 

 at the base; leaves petioled, simple or pinnate, with small lateral leaflets; blade 

 or terminal leaflet ovate or elliptic, 1-4 cm. long, dentate or entire, glabrous, 

 veiny; tube of the hypanthium 2-3 mm. long; petals bright yellow, 3-5 mm. 

 long; capsule 1.5-2 cm. long, 2 mm. thick. O. scapoidea Nutt. Hills and river 

 banks: Wyo. Colo. Ariz. Calif. Ore. Son. Submont. 



3. C. cruciformis (Kellogg) Howell. Stem 2-4 dm. high, finely puberu- 

 lent or glabrate; leaves interruptedly pinnate; leaflets 5-15, lanceolate or ovate, 

 0.5-4 cm. long, veiny; tube of hypanthium 4-5 mm. long; petals 7-10 mm. long; 

 capsule about 2 cm. long, 2 mm. thick. 0. cruciformis Kellogg. Dry regions: 

 Ore. Colo. Ariz. Calif. Son. Mr-Je. 



4. C. brevipes (A. Gray) Small. Stem branched at the base, 2-3 dm. high, 

 usually densely white-hirsute; leaves simple, or pinnate with small lateral leaf- 

 lets; blade or terminal leaflet ovate, 3-5 cm. long, dentate, veined, hirsute; tube 

 of the hypanthium 5 mm. long; petals yellow; capsule spreading on short pedi- 

 cels. 0. brevipes A. Gray. Arid regions: s Utah Ariz. Calif. Nev. Son. 

 Ap-Je. 



5. C. Parryi (S. Wats.) Small. Stem branched, 2-3 dm. high, sparingly 

 ciliate; leaves simple, petioled; blades ovate or oblong-lanceolate, 2-5 cm. long, 

 entire or sinuate, pubescent with scattered long spreading hairs, especially on 

 the veins; free tube of hypanthium 1 mm. long; petals yellow or orange, 6-7 mm. 

 long; capsule 8-12 mm. long, ascending. Clayey hills: s Utah. L. Son. 



6. C. tenuissima (M. E. Jones) Rydb. Stem much branched, 3-10 dm. 

 high; leaves mostly simple; blade lanceolate, sparingly dentate, acute at each 

 end, veiny beneath, sparingly pilose, about 1 cm. long; inflorescence racemes or 

 panicles, axillary, with ascending-spreading branches; tube of the hypanthium 

 about 1 mm. long; petals 2-5 mm. long, yellow; capsule clavate, 4-6 mm. long, 

 on divergent pedicels. 0. tenuissima M. E. Jones. Barren clay soil: Utah. 

 Son. S. 



7. C. Walkeri A. Nels. Stem slender, 1-2 dm. high, minutely glandular- 

 pubescent and with some long white hairs; leaves simple, entire, ovate to oblong- 

 lanceolate, white-hirsute; tube of hypanthium 0.5 mm. long; petals yellow, oval; 

 capsule clavate, 10^14 mm. long, on a filiform spreading pedicel of the same 

 length. Gypsum hills: w Colo. Son. Jl. 



8. C. venosa Nels. & Kenn. Stem 3-5 dm. high, villous, becoming gla- 

 brate in the inflorescence; leaves 1-2 dm. long, interruptedly pinnate; terminal 

 leaflet orbicular or ovate, 2-4 cm. long, finely canescent above, hirsute beneath, 

 veiny, irregularly serrate; the lateral ones smaller and lanceolate; tube of hy- 

 panthium 2.5 mm. long; petals yellow, turning purple, 8 mm. long; capsule 2 

 cm. long, almost glabrous. Canons and river valleys: Nev. Utah. Son. 

 My-Je. 



9. C. parviflora (S. Wats.) Rydb. Annual; stem 2-3 dm. high, glabrous 

 or sparingly pubescent; leaves interruptedly pinnate, glabrous or nearly so; 

 terminal leaflet ovate, 2-4 cm. long, sharply serrate, strongly-veined, the lateral 

 ones lanceolate, smaller; tube of hypanthium 2 mm. long or less; petals light yel- 

 low, 4-6 mm. long; capsule about 3 cm. long, 2 mm. thick. 0. brevipes parviflora 

 S. Wats. Arid regions: s Utah Ariz. L. Son. 



9. C. multijuga (S. Wats.) Small. Stem branched, glabrous, 2-3 dm. 

 high; leaves interruptedly pinnate; larger leaflets 12 pairs or more, of nearly 



