1905] NELSON—ROCKY MOUNTAIN PLANTS 59 
oblanceolate and tapering into a slender petiole; all of them hirsute 
with white spreading hairs: flowers axillary from the base up; calyx 
tube very short, the lobes lance-oblong, 3-4™™ long; petals broadly 
ovate-oblong, tridentate at the nearly truncate summit, about twice 
as long as the calyx-lobes, exceeding the longer stamens and about 
equalled by the pistil: capsules purplish, small and slender, less than 
2°™ long, variously flexed and somewhat angled: seeds small, pale, 
smooth, usually oblique at base and obliquely pointed at apex. 
I name as type A. D. E. Elmer’s no. 3192, Monterey, Cal., distributed as 
S. micranthum. No. 5099, by C. A. Purpus, seems to be the same. 
10. S. HIRTELLUM (Greene) Small, Bull. Torr. Bot. Club 23: 190; 
Oenothera hirtella Greene, Fl. Francis. 215.—LE&VEILLE in his mono- 
graph reduces this to a form of S. micranthum, but this does not 
seem to be justified by his specimens. 
11. S. MICRANTHUM (Hornem.) Walp. Repert. 2:77; Ocenothera 
micrantha Hornem. Hort. Hafn.—That LE&vEILLE should take up 
the much later name O. hirta, and then reduce to this species such 
distinct forms as S. hirtellum, and S. Nelsonii, seems a little strange. 
However, he has described a very good variety which may be written 
11a. S. MICRANTHUM Jonesi (Lévl.), n. comb.—Taking as the 
type the first number cited, viz. Hansen’s 543, Amador Co., Cal. 
1892, I would name as a close duplicate C. C. Parry’s specimens 
(in the Missouri Botanical Garden) simply labelled ‘Oenothera. 
June 1889. Cal.’’ Blanche Trask’s Avalon specimen, cited by 
LEVEILLE, seems rather to belong with the species itself. It is quite 
probable that the species as it now stands is an aggregate. 
11b. S. MICRANTHUM exfoliatum, n. var.—Branched from the 
base, the stems stoutish, the bark white, shreddy, and exfoliating in 
thin sheets, giving the plant the appearance of S. decorticans: pubes- 
cence of the stems ciliate, that of the leaves and fruits closer and 
somewhat appressed: capsules sharply angled, contorted. : 
I cite here the following specimens: C. R. Orcutt, Colorado Desert, April, 
1889; C. A. Purpus, no. 5083, Erskine Creek, Cal., 1897. 
12. S. Bistortum (Nutt.) Walp., Repert. 2:77. Ocenothera 
bistorta Nutt., T. & G. Fl. N. A. 1:508. 
12a. S. Bistortum Veitchianum (Hook.), n. comb.; Oenothera 
bistorta Veitchiana Hook., Bot. Mag. pl. 5078—The characters 
