564 ONAQRACEAE 



type loc. Kern Canon, Culbcrtson 4220. Z. pulchella Moxley, Southwest Sci. Bull. 1:27 (1920), 

 tvpe loc. Willouplibv Mine, Gold Lake region, Plumas Co., E. C. Sutliffe. Z. pulchella var. ad- 

 pressa Moxlev, BulI."S. Cal. Acad. 20:54 (1921), type loc. Salmon Lake, Sierra Co., E. C. Sutliffe. 

 Z. orbiculai a' Uoxloy, Bull. S. Cal. Acad. 19*: 30 (1920), type loc. Saw Mill Canon, Inyo Co., e. 

 slope Sierra Nevada, Pcirson 759. Z. calif ornica var, johnstonii Hilend, Am. Jour. Bot. 16:67 

 (1929), type loc. 6 mi, se. of Poppet Flat, San Jacinto Mts., Muns Sr Johnston 8836. Var. 

 TOMENTELLA Jcpson, Man. 667 (1925). Z. tomentclla Greene, Pitt. 1:26 (1887), type loc. Yosem- 

 ite. Z. canesccns Eastw. Southwest Sci. Bull. 1:29 (1920), type loc. South Fork Kaweah River, 

 Culbcrtson 4502. Var. viscosA Jepson, Man. 667 (1925). Z. viscosa Moxley, Bull. S. Cal. Acad. 

 15:22 (1916), type loc. summit of ridge near Barley Flats, San Gabriel Mts., Moxley 412. Z. 

 hallii Moxley, Southwest Sci. Bull. 1:27 (1920), type loc. ridge w. side San Jacinto Mts., Hall 

 2567 (vidi typ.), 



4. EPILOBIUM L. Willow Herb 



Herbs; annual, perennial by creeping rootstocks, or propagating in the autumn 

 by offsets. Leaves opposite or alternate. Flowers purple, rose-color or white, 

 borne in racemes or panicles. Calyx-tube short or none. Sepals 4. Petals 4, 

 often emarginate or bifid. Stamens 8, the 4 alternate shorter. Stigma oblong or 

 4-lobed. Ovary long and narrow, 4-celled. Capsule 4-valved. Seeds numerous, 

 the summit bearing a tuft of long hairs (coma) . — Species about 160, all continents. 

 (Greek epi, upon, lobus, a pod, and ion, a violet.) 



Bibliog. — Haussknecht, C, Epilobia nova (Oesterr. Bot. Zeitschr. 29:89-91, — 1879) ; Mono- 

 graphie der Gattung Epilobium, 1-318, t. 1-23 (1884). Trelease, W., A revision of the Am. 

 species of Epilobium occurring north of Mexico (Eep. Mo. Bot. Gard. 2:69-117, pis. 1—48, — 

 1891). Leveille, H., Iconographie du genre Epilobium, 1-328, pis. 1-272 (1910-1911). Fernald, 

 M. L., American variations of Epilobium, sect. Chamaenerion (Rhod. 20:1-10, — 1918); Some 

 Am. EpUobiums of the sect. Lysimaehion (Ehod. 20:29-39, — 1918). 



A. Petals entire, 5 to 9 lines long, spreading, slightly irregular, flowers large; calyx divided down 



to the ovary or nearly, the tube none or almost none; style at first recurved; stigma 



4-cleft; capsules long-pediceled; leaves alternate; perennials with stout 



horizontal rootstocTcs. — Subgenus Chamaenerion. 



Racemes many-flowered, elongate, not leafy; petals purple; leaves green above but pale and veiny 

 below 1. E. angustifolium. 



Racemes few-flowered, short, very leafy; petals rose-color; leaves pallid and veinless on both 

 surfaces 2. E. latifolium. 



B. Petals deeply notched or obcordate, ascending, regular; calyx deeply divided, the tube u,sually 



short but always evident; style not curved. — Subgenus Lysimachion. 



Perennials; leaves opposite or mainly so (often more or less alternate in no. 10). 



Flowers large, the petals ^/^ to 1 inch long ; stigma with oblong lobes ; low plants. 



Leaves 3 to 5 lines long (except var.), crowded; calyx-tube 1% to 2 lines long; alpine or 

 high montane, Sierra Nevada, and Siskiyou and Trinity Cos.. .3. E. obcordatum. 



Leaves 1 to 1^/^ inches long, discrete; calyx-tube i/^ line long; low hills, Del Norte Co 



4. E. rigidum. 

 Flowers small, the petals 1 to 6 lines long ; stigma entire or rarely lobed. 



Leaves tipped with a brown subulate gland; stem arising from a short woody caudex; 



xerophilous 5. E. nivium. 



Leaves not gland-tipped ; usually springy or boggy ground. 



Plants pallid, glabrous and glaucous 6. E. glaberrimum. 



Plants green and not at all glaucous. 



Rootstocks not producing fleshy-scaly buds. 



Stems 2 to 12 inches high, simple, stolonif erous ; high montane. 

 Leaves more or less spreading. 



Stems many from a much-branched root-crown ; leaves elliptic to 



narrow-ovate, thickish, 3 to 4 lines wide 



7. E. anagallidifolium. 

 Stems few to many from a slender horizontal rootstock; leaves 



elliptic to oblong-ovate, very thin, 5 to 8 lines wide 



8. E. alpinum. 

 Leaves ascending or strictly erect, linear to ovate-oblong, 3 to 8 lines 



long 9. E. oregonense. 



Stems 1 to 4 feet high, almost always branched above, not stolonif erous ; 

 foothills and lower valleys. 



