LOASA FAMILY 529 



5. M. involucrata Wats. Samija. Stems branching, with verj^ white bark, 

 3 to 24 inches high; herbage hispid with stiff hairs; leaf -blades linear to oblong- 

 lanceolate or -oblanceolate, coarsely sinuate-dentate, 2 to 61/2 inches long, the lower 

 attenuate into a petiole, the upper sessile and clasping; flowers solitary, terminal, 

 closely subtended by a pair of broad white searious bracts with deeply laciniate- 

 toothed green margin; petals obovate, abruptly acuminate, light straw-color with 

 a satiny sheen, a tinge of crimson in center, {% or) 1 to 21/2 inches long; stamens 

 numerous, slender, I/2 as long as the petals, the outer dilated above and continued 

 with a long cusp on each side of the anther; capsule 9 to 12 lines long, 3 lines broad 

 at apex; seeds irregularly oval or roundish-quadrangular, rugulose and minutely 

 granular. 



Sandy or gravelly washes and rocky caiion sides, -50 to 800 feet: Colorado 

 Desert. East to Arizona, south to Mexico. Feb. -Apr. 



Locs. — Eagle Mts., Munz 4- Keck 4940 ; Cottonwood Spr., Cottonwood Mts., Jepson 12,552 ; 

 Dos PalmOS Spr., Munz 9951; Mecca Hills, Jepson 11,646; Coral Eeef Canon, Coachella, Clary 

 1596; "Whitewater, Jepson 11,620; betw. Pinon Well and County "Well, Jepson 6009; Palm Caiion 

 of San Jacinto, Jepson 1353; Borrego Spr., Jepson 8882; Signal Mt., T. Brandegee; Coyote 

 Wells, Newlon 390. 



Eefs. — Mentzelia involucrata Wats. Proc. Am. Acad. 20:367 (1885), type loc. San Ber- 

 nardino Co., Parry; Jepson, Man. 649 (1925). Bicuspidaria involucrata Eydb. Bull. Torr. Club 

 30:275 (1903). Nuttallia involucrata Dav. & Mox. (by error "Watson"), Fl. S. Cal. 240 (1923). 

 M. involucrata var. megalantha Jtn. "Clniv. Cal. Publ. Bot. 7:443 (1922), type loc. near Salton, 

 Eiverside Co., Hall 5839. Nuttallia involucrata var. megalantha Dav. & Mox. (by error "Munz 

 & Jtn."), Fl. S. Cal. 240 (1923). 



6. M. peirsonii Jepson sp. n. (Fig. 248.) Stem diffusely and repeatedly 

 branched from the base, 6 to 11 inches high; leaf -blades ovate, 1 to IVo inches long, 

 sinuately and saliently few-toothed with lanceolate teeth, sessile or subcordately 

 clasping, the lower or basal oblong and petioled; calyx-lobes 6 to 7 lines long; 

 petals obovate, acuminate or acute, pale yellow-slate color, 8 to 9 lines long; 2 or 

 3 outer rows of filaments linear, the anthers set in a notch at apex; capsules linear, 

 10 to 12 lines long, 2^4 to 21/2 lines wide. — (Caules basi diffuse, iteratim ramosi, 

 unc. 6-11 alti; folia ovata, unc. 1-1^ longa, sinuate et saliente paucidentata den- 

 tibus lanceolatis, sessilia vel subcordate amplexicaulia, inferiora oblongata, petio- 

 lata; calycis lobi lin. 6-7 longi; petala obovata, acuminata vel acuta, palliflaventia, 

 lin. 8-9 longa; verticillorum exteriorum filamenta linearia apice serrata; capsulae 

 lineares, lin. 10-12 longae, lin. 21^-21/2 latae.) 



Sandy washes, 800 feet : west side of Colorado Desert in southwestern Imperial 

 Co. Apr. 



Loc. — Myers Creek bridge, foot of Mountain Springs grade, Jepson 11,764 (type), F. W. 

 Peirson. 



7. M. tricuspis Gray. Desert Stick-leaf. Stems branching from or near the 

 base, 3 to 10 inches high; herbage hispidulous; leaf -blades narrow-oblong to ovate or 

 oblanceolate, saliently toothed or serrate to subentire, 1 to 2 inches long, attenuate 

 at base into a short petiole; flowers terminal on short branches; calyx lobes filiform- 

 subulate from a triangular base, becoming involute and caudiform-rotate or re- 

 flexed after anthesis, (2i/^ or) 41/2 to 7 lines long; petals light yellow-slate color, 

 narrow-obovate, sharply apiculate, 6 to 10 lines long; stamens in 4 or 5 rows, the 

 2 outer rows with dilated filaments, the anthers borne on a short filiform prolonga- 

 tion in the acutely notched apex; capsule oblong, hirsute, papillate-tesselated, 5 

 to 6 (or 11) lines long, 2 to 2^2 lines wide, in age reflexed; seeds broadly oblong, 

 rugose, and with 2 or 3 deep narrow irregular channels or folds, 1 line long. 



Stony hills, 200 to 3200 feet : eastern Mohave Desert. East to Nevada and 

 Arizona. Apr. 



Locs. — Yermo, Jepson 15,867a; Barstow, Jepson 5828; Old Woman Sprs., s. Mohave Desert, 

 Jepson 5951; Needles (Dav. & Mox. Fl. S. Cal. 240). 



