EVENING PRIMROSE FAMILY 



589 



2. 0. trichocalyx Nutt. Basket Evening Primrose. (Fig. 256.) Stem 

 simple, short, very thick or even conical, 1 to 2 (or 6) inches high, very densely 

 flowered, commonly developing from beneath this short dense spike several ascend- 

 ing stems 4 to 14 inches (or even 2i/^ feet) high which are loosely flowered above, 

 and sparsely pilose or almost glabrous; leaf -blades oblong to ovate or lanceolate, 

 tapering to both ends, subentire or rather remotely denticulate to coarsely and 

 saliently toothed or lobed, canescent or pilose, 1 to 7 inches long, margin at first 

 undulate, shortly petioled; calyx-tube % to li/4 inches long; calyx-tips not free in 

 the bud; bud (just before anthesis) oblong, woolly-pilose; petals % to li/4 inches 

 long, usually with a deep sinus; capsules very slender, terete, thickened towards 



the broad sessile base, slightly curved or nearly 

 straight, widely spreading or in maturity 

 strongly deflexed, woody, 1% to 3 (or 4) inches 

 long; seeds narrowly ovate, mottled, somewhat 

 compressed. 



Sandy washes or benches and dry mesas, 

 -125 to 1700 feet : upper San Joaquin Valley 

 in Kern Co.; Mohave and Colorado deserts. 

 South to Lower California, east to Wyoming 

 and Mexico. Mar.-June. 



Field note. — The most marked natural type be- 

 haves as follows : Initially the stem or primary axis is 

 simple, erect, rather short, strongly dilated and rather 

 densely flowered. If the conditions continue favorable 

 for growth secondary or lateral axes are developed in 

 a whorl from the base of the main stem, the flowering 

 portion of these secondary axes becoming markedly 

 dilated. Both the central axis and the laterals are un- 

 branched. Sometimes the entire expression of the plant 

 is thrown into the primary axis and we have a stem 

 2 feet high, strongly inflated (% to 1 inch in diameter) 

 and floriferous and leafy from base to apex. 



In 1930 a very large number of fasciated plants, 

 perhaps one hundred, were found near Lavic (west 

 several miles, by the railway line) scattered over a dis- 

 tance of one-fifth mile. We observed that only the 

 central axis was fasciated, this fasciation being ribbon- 

 like. One plant, for example, measured 21 inches high, 

 the ribbon being 9 inches wide at the top. Another plant 

 12 inches high developed a ribbon 16 inches wide. 

 Locs. — Kern Co.: Bakersfield plain, Jepson 8942. Mohave Desert: Lancaster, Elmer 3810; 

 Kramer, Jepson 5344; Barstow, Jepson 5184; Calico Wash, n. of Daggett, Jepson 5406; Lavic, 

 Jepson 15,473; betw. Halloran Sprs. and Windmill sta., Jepson 15,801; Needles, Jones 3870. 

 Colorado Desert: Palm Sprs. of San Jacinto, Parish 4107; Borrego Sprs., T. Brandegee; San 

 Felipe Wash, Jepson 8897; Carrizo Creek, T. Brandegee; Brawley, W. S. Childs; Holtville (plain 

 e.), Jepson 11,719. 



Var. cognata Jepson. Stems coarse, branching; leaves green and glabrate above and be- 

 low, or tending to be so, the margins hirsute-ciliate ; flowering axes less dilated or not at all. — 

 Sandy fields or stream bottoms, 10 to 400 feet : inner South Coast Eanges, ranging west to the 

 Nacimiento Eiver; San Joaquin Valley. 



Locs. — South Coast Eanges: Corral Hollow, Alameda Co., Brewer 1217; San Miguel Eiver, 

 Bhoda Reed 467. San Joaquin Valley: Antioch, K. Brandegee; betw. Mossdale and Atlanta, San 

 Joaquin Co., Jepson 14,479; Delhi, Merced Co., Jepson 12,745; Huron, Fresno Co., T. Brandegee; 

 Bakersfield, Davy 1735. 



Var. cineracea Jepson. Leaves finely strigulose with short appressed hairs. — ^Western Colo- 

 rado Desert: Borrego Sprs. 



Var. piperi Jepson comb. n. Plants usually low, 4 to 6 inches high, the stems often simple; 

 pubescence on upper portions long, arcuate; upper leaves deeply and regularly sinuate-dentate 

 to pinnatifid; petals about % inch long; capsules V2 to li/4 inches long.— Sandy flats or slopes, 

 3000 to 4000 feet : east slope of Sierra Nevada and east or north of its crest from Inyo Co. to 

 Siskiyou Co. North to eastern Oregon, east to western Nevada. 



Fig. 256. Oenothera trichocalyx 

 Nutt. a, habit, X Ve ; i, long. sect, of 

 fl., X V2; c, capsule, X %. 



