912 CARDUACEAE 



Pappus copious, in fruit elongating and surpassing the styles. 



Pannus-bristles in several series; plant 3-6 dm. high, herbaceous, with a woody base. 



1. B. Wrightii. 

 Pappus-bristles in one series; plants 1-5 mm. high, shrubby. 



Fertile heads hemispherical, 5-10 mm. broad; bracts all acute. 2. B. salicina. 

 Fertile heads deeply campanulate, 3-5 mm. broad; outer bracts obtuse. 



3. B. Emoryi, 

 Pappus scant, little if at all elongating, in fruit not exceeding the styles. 



Achenes 10-nerved; leaves less than 2 cm. long, suben^ire. 4. B. sergiloides. 



Achenes 5-nerved; leaves 5-15 cm. long, serrate. 5. B. glutinosa. 



1. B. Wrightii A. Gray. Herbaceous, with a woody base; stems diffusely 

 branched, 3-6 dm. high, glabrous and angled; lower leaves linear, 2-4 cm. long, 

 glabrous, the upper 'smaller and linear-subulate; involucres of the staminate 

 heads about 7 mm. high, 10-12 mm. broad; bracts in 3 series, lanceolate, acute, 

 erose-ciliate on the margins; involucres of the pistillate heads 8-10 mm. high, 

 12-15 mm. broad; bracts in 5-6 series, with more evident scarious margins; 

 achenes oblong, 8-10-ribbed, scabrous, puberulent and cross-rugose; pappus 

 brownish, 10-12 mm. long. Saline soil : Kans. Colo. Ariz. Mex. Son. Ap- 

 Je. 



2. B. salicina T. & G. Shrub 1-4 m. high; branches green and glabrous, 

 angled; leaves oblong or oblong-lanceolate, denticulate or entire, 3-5 cm. long; 

 heads in small clusters; involucres of the staminate heads hemispheric, 4-5 mm. 

 high and slightly broader; bracts in 4-5 series, ovate, yellowish green, glabrous, 

 erose-ciliate on the margins; involucres of the pistillate heads 6-8 mm. high and 

 broad, the inner bracts lanceolate; achenes 10-ribbed, glabrous; pappus white 

 and soft, 10-12 mm. long. Saline soil: Kans. Utah N.M. Tex. Son. Je-Jl. 



3. B. Emoryi A. Gray. A shrub 1-5 m. high; branches very glutinous, gla- 

 brous, slightly angled; leaves linear-oblong, entire, 2-5 cm. long, or the larger 

 broader, somewhat 3-ribbed and somewhat lobed, glabrous; heads more or less 

 glomeruled; involucres of the staminate heads campanulate, 5-6 mm. high, 4 

 mm. wide; bracts ovate, acute, thick, in 6-7 series; involucres of the pistillate 

 heads 6-8 mm. high, 4-5 mm. broad; bracts in 7-8 series; achenes glabrous, 

 10-ribbed; pappus tawny, nearly 1 cm. long. Along rivers: Tex. s Utah Calif. 

 Son. 



4. B. sergiloides A. Gray. A shrub 1-2 m. high; branches glabrous, strongly 

 angled, and broom-like; leaves few, oblanceolate, 5-15 mm. long, soon caducous 

 or wanting; heads paniculate; involucres of the staminate heads 3-4 mm. high 

 and as broad, those of the pistillate heads 4-5 mm. high; bracts ovate to lanceo- 

 late, acute, glabrous in about 5 series, thick; achenes glabrous, 10-nerved, 1.25 

 mm. long; pappus tawny, 3^ mm. long. Arid regions: Ariz. s Utah s Calif. 

 L. Son. 



5. B. glutinosa (R. & P.) Pers. Plant herbaceous above, woody below; 

 stem 1-3 m. high; branches striate, glabrous; leaves elongate-lanceolate, 5-15 

 cm. long, 3-nerved, serrate, or the upper entire; heads numerous, corymbosely 

 cymose; involucre both in the staminate and the pistillate heads 4-5 mm. high 

 and broad, hemispheric; bracts ovate, acute, in 4-5 series, glabrous, erose-ciliate; 

 achenes glabrous, 5-nerved; pappus white, 4 mm. long. Along streams: Tex. 

 Colo. Calif.; Mex. and S. Am. Son. Mr-N. 



49. BERTHELOTIA DC. 



Very leafy silyery-canescent shrubs. Heads glomerate. Involucres cam- 

 panulate; bracts imbricate, chartaceous, the innermost narrowly linear and 

 falling off with the flowers. Receptacle flat, naked and glabrous. Marginal 

 flowers pistillate, numerous, their corollas with a filiform truncate tube, with- 

 out ^ligules; style-branches without appendages. Central flowers perfect, but 

 sterile; their corollas tubular, regularly 5-lobed; styles with entire tips. Achenes 

 4-5-angled. Pappus of the marginal flowers of a series of capillary bristles; 

 pappus-bristles of the central flowers shorter and with clavellate tips. 



1. B. sericea (Nutt.) Rydb. A shrub 2-3 m. high, much branched; branches 

 silky tomentose; leaves entire, linear-lanceolate, sessile, acute at each end, 1-3 



