Cnicus. compositjl. 403 



= Leaves pinnately parted into narrow and linear mostly entire divisions : antlier-tips attenuate- 

 subulate. 



C. Pitcheri, Tore. A foot or two high, ivith herbage persistently whlte-tomentose throno-b- 

 oiit : lower leaves a foot or so long, with di\ i>i..n~ (-2 to 4 inches long, 2 or .3 lines wide) 

 either entire or some again pinnately parted into shorter lolies, weakly prickly-tipped; the 

 ivinged rhachis not wider than the divisions : heads few or solitarv, 2 inches high : involucre 

 glabrate ; the bracts ratlier small, visiid down the back, tipped with small short prickle : 

 corollas ochroleucous. — Torr. in A. Eaton, Man. ed. .), 180; Grav, Proc. Am. Acad. x. 42. 

 Virsium Pitcheri, Torr. & Gray, Fl. ii. 456. — Sand-banks on the shores of the Great Lakes 

 from the head of Lake Michigan northwestward, and in Dakota, .Swljfii ; fir.-t coll by 

 JJr. Pit, her. 



= = Leaves from undivided to pinnately parted, the lobes lanceolate or broader, disposed to be 

 w'.ute-tomentose above as well as below: prickle on cusp of the principal involucral bjacts more 

 or less ri;^id and pungent. 



u. Bracts of the involucre minutely scabrous-ciliolate. 

 C. Grahami, Gray, stem 3 to 8 feet high ; leaves elongated-lanceolate (larger ones a foot 

 or more long), from repand-dentate to sinuate and pinuatifid (sometimes delicatelv, .some- 

 times strongly prickly), upper face at length glabrate and green : heads 1 J to :;; inches Li-lj : 

 involucre glabrate and greenish ; the bracts lanceolate-subulate, tipped iv'itli a .".hort ri:;id 

 cusp rather than prickle, the margin^ at least of the principal cues minutely scabrou.s<'iliolate : 

 corollas crimson-red: anther-tijjs attenuate-subulate. — Proc. -\ra. Acad. .xix. 57. C. undti- 

 latus, var. Grahami, Gray, Proc. Am. Acad. x. 43. Cirsinm Grahami, Gray, PI. Wright, ii. 

 102; Hijok. Bot. Mag. t. 288.0. — Wet ground, Arizona, Wright, Thurber, L<mmon. 



h. Bracts of the involucre smooth and naked, or else tomentose on the margins. 



C. Och.rocentrus, Gr.w. Resembles the next following species, usually taller, even to 6 

 or 8 feet high, the white tomentum mostly persistent : leaves commonly but not always 

 deeply piunatifid and armed with long yellowish prickles : heads 1 or 2 inches high : princi- 

 pal bracts of the involucre broader and flatter, the viscid line on the back narrow or not 

 rarely obsolete, tipped with a prominent .spreading yellowish prickle: corollas purple, rarely 

 white. — Proc. Am- Acad. xix. 57. C. undtilatus, var. orhrocentrus, Gray, I'roc. -Vm. .\cad. 

 -x. 43. f'irsium ochrocentrum. Gray, PI. Fendl. 110. — Plains, &c., W. Texas to Colorado, the 

 eastern Sierra Xevada, and Arizona. (Adj. Mex.) 



"C. undulatus Gr.vt. A foot or two high, persi~tently white-tomentose : leaves rarely pin- 

 natelv parted, moderatelv prickly: heads commonly inch and a half high: principal bracts 

 of the involucre mostly thickened on the back by the broader glandular-viscid ridge, com- 

 paratively small and narrow, tipped with an evident ipreadihg slmrt prickle : corolla^ ro^e- 

 color, pale purple, or rarely white; its lobes equalling or surpa<>ing the throat in length: 

 anther-tips attenuate-subulate. — Proc. Am. Acad. x. 42, excl. var. oclirocentrvs, & var. Gni- 

 hami. Carduus undulatus, Xutt. Gen. ii. 130. C. discolor. Hook. PI., in j.art. C. L><tiir/!asii, 

 DC. Prodr. vi. 643, excl. habitat. Cirsium Hookerianum, Hook. Lond. .Jnur. Bot. vi. 253, 



not Xutt. Plains, &c., from Lake Huron and Minnesota to Saskatchewan, west to C>regon, 



south to Kansas and Xew Mexico. 



--. Var. canescens. Gray, 1. c, is merely a form with smaller heads, sometime? not 

 over an inch high, the leaves varying from ciliately spinulose-dentate to deeply piunatifid. — 

 Cirsium canescens & C. bret-ifolium. Xutt. Trans. Am. PhiL Soc. vii. 42L — iliuuesota to Xew 

 Mexico and S. L'tah. 



Var. megacephalus, Gray, 1. c. Stnuter form, usually broader-leaved, with Ijroad 

 heads 2 inches or more high — Jlinnesota and Texas (where coll. Ijy Berlundier) to Idaho. 

 C. Breweri, Gray, 1. c. Usually both very white-tomentose and tall (5 to 10 feet high) : 

 leaves mostly elongated-lanceolate, conspicuously prickly: lieaJs paniculate, sometimes very 

 numerous, subspssile, merely inch high, or when solit.iry inch and a half high : .bracts of the 

 globular involucre much apjiressed, firm-coriaceous, the tip externally bearing an oval or 

 oblong greenish viscid-glandular spot; outer ones ovate to oblong, abruptly tipped with a 

 rather slender sjireading prickle : corollas pale purple or whiti-h, the lobes shorter than the 

 throat: anther-tips deltoid, merely acute. — S],riiigy soil. Sierra Xevada from Lake Tahoe 

 and :iIendocino Co., California (first coll. by An,l,rson and Breu-rr), to E. Oregon, Cusick, 

 &c. Also, less wliite-wooUv, San Juan, :Mouterey Co., Bn.rer, leading to the var. 



