EVENING PRIMROSE FAMILY 



591 



long; petals yellow, aging pinkish, 1 to 1% inches long; capsules oblong-ovate or 



oblong-lanceolate, strongly 4-sided or quadrangular, straight or only very slightly 



curved, with a round or acutish ridge on the angles, 1 to 1% inches long; seeds 



irregularly tuberculate. 



Sandy soil, 2000 to 3000 feet : Inyo Co., south through the Mohave Desert to 



the Colorado Desert, then entering San Gorgonio Pass. East to western Texas, 



south to IMexico and Lower California. Mar.-May. 



Locs. — Inyo Co.: Darwin Mesa, R. S. Ferris 7835. Mohave Desert: Goffs, Parish 9646; 



Barstow, Jepson 6146; Kramer, Jepson 5342; betw. Eandsburg and Kand, Kern Co., K. Bran- 



degee; Mohave sta., F. P. Morse. Colorado Desert: 

 Shavers Well (Am. Jour. Bot. 18:736). Cismontane 

 S. Cal.: Banning, San Gorgonio Pass (Am, Jour. Bot. 

 18:736). 



Eefs. — Oenothera primiveris Gray, PI. Wright. 

 2:58 (1853), type loc. El Paso, Tex., Wright 1376; 

 Jepson, Man. 682 (1925). Lavauxia primiveris Small, 

 Bull. Torr. Club 23:182 (1896). 0. caespitosa var. 

 primiveris Levi. Monog. Onoth. 71 (1902). 0. bufonis 

 Jones, Contrib. West. Bot. 8:28 (1898), type loc. Dar- 

 win Mesa, Argus Mts., Jones. Lavauxia lobata Nels. 

 Bot. Gaz. 47:429 (1909), type loc. Meadow Valley 

 Wash, s. Nev., Goodding 37, 47. 



5. 0. xylocarpa Cov. Kern Evening 

 Primrose. (Fig. 257.) Leaves and sessile 

 flowers borne in a tuft on the crown of the very 

 stout root; leaf -blades elliptic to ovate, obtuse 

 or acute, ^2 to 2^4 inches long, commonly with 

 several small irregular supplementary lobes at 

 base and thus lyrately pinnatifid, puberulent; 

 petioles longer than the blades or nearly as 

 long; calyx-tube 1 to 2 inches long; petals yel- 

 low, aging orange-red, 1 to l^/^ inches long; 

 capsules thick-lanceolate, long-attenuate, 

 curved or contorted, 2i/2 to 3 inches long, the 

 angles developed into thick somewhat undulate 

 wings, the back of each valve prominently 

 ribbed ; seeds minutely tuberculate. 

 Sandy or gravelly flats, 8000 to 9800 feet : Sierra Nevada from eastern Tulare 

 Co. to Mono Co. East to western Nevada. June- Aug. 



Field note. — The flowers open most freely at five o'clock in the afternoon, remaining open all 

 night, some of them remaining open all the next day. The corolla is white, turning yellow after 

 anthesis and finally pink-red, being closed or half -closed after the white stage. The midvein of 

 the obcordate petals is carinate on the upper surface in such a way that the petals are not plane, 

 so that the flower in aspect is different from the flowers of the allied species. — Jepson Field Book, 

 25:101, ms.. Volcano Creek, July 3, 1912. 



Locs.— Fish Creek, se. Tulare Co., Ball 4- Bahcock 5214; Ground-hog Mdw., Volcano Creek, 

 Kem Eiver, Jepson 4948; Bishop (35 mi. n.). Mono Co., Muns 11,084. 



Eefs.— Oenothera xylocarpa Cov. Contrib. U. S. Nat. Herb. 4:105, pi. 8 (1893), type loc. 

 Whitney Mdws. (Volcano Mdws.), Tulare Co., B. E. Butcher; Jepson, Man. 682 (1925). Anogra 

 xylocarpa Small, Bull. Torr. Club 23:174 (1896). 



6. 0. caespitosa Nutt. (Fig. 258.) Leaves in a basal rosette, these and the 

 flowers borne in a tuft on the short axis of the root-crown; herbage green, pilose- 

 pubescent or glabrate; leaf -blades ovate to lanceolate in outline, coarsely and irreg- 

 ularly or often sparsely dentate, sometimes subentire, 1 to 4 inches long, narrowed 

 to a petiole half to as long ; flower-buds strongly 4-sided ; tips of calyx-lobes not 

 free in the bud ; calyx-tube 3 to 51/2 inches long, dilated upward into a narrow- 

 funnelform dilation; petals white, turning pink, 1 to 1% inches long; capsules 

 oblong or linear to narrow-ovate, obtusely quadrangular, 1 to 1% inches long, the 



Fig. 257. Oenothera xylocarpa 

 Cov. a, habit, X % ; &, stigma, X 2 ; c, 

 dehiscing capsule, X %. 



