132 Rydberg : Rocky Mountain flora 



Carduus perplexans sp. nov. 



Rather slender, about 5 dm. high ; stem striate, purplish, 

 slightly tomentose ; lower leaves oblanceolate, the upper lanceo- 

 late and clasping, all merely toothed, with weak yellowish spines, 

 glabrous and somewhat glaucous above, rather thinly white-tomen- 

 tose beneath ; heads about 3 cm. high and broad ; bracts well im- 

 bricated, usually with a glandular back, the outer shorter and 

 tipped with a short weak spine, the inner tipped with a dilated, 

 deltoid, erose appendage ; corolla rose or red-purple. 



The appendages of the bracts would place this species nearest 

 C. Ccntanrcae, but the bracts are broader and have a distinct 

 glandular back, the corolla is pink or purplish, and the whole 

 plant suggests C. altissiniiis and its relatives. In fact the species 

 combines characters of the Carliiioidcs and the Altis'iiiiuis groups. 

 It grows at an altitude of nearly 2100 m. 



Colorado: Cimarron, xgox, Bakcj- 2S6. 



Carduus coloradensis sp. nov. 



Cnicus Dniuiuiotidii A. Gray Syn. Fl. i" : 402, in part, /. c, as 



to the Colorado specimens. 



Rather stout, simple, 3-5 dm. high ; stem striate, sparingly 

 arachnoid; leaves 1.5—2 dm. long, 4-7 cm. wide, linear or oblong; 

 in outline, pinnately lobed about half-way to the midrib, spar- 

 ingly arachnoid above, more or less white-tomentose beneath ; 

 lobes ovate, tipped with yellowish spines 2—5 mm. long and bor- 

 dered with smaller spines ; heads 3-4 cm. high and about as 

 broad ; bracts glabrous or nearly so, firm, more or less yellowish, 

 without dorsal glandular ridge, well imbricated in many unequal 

 series ; the outer with weak spines ; the inner unarmed and with 

 slightly dilated crisp tips ; corolla white or slightly pinkish. 



This species has gone under the name of C. Drmninoiidii, but 

 the latter has larger heads often 5 cm. high and broad, broader and 

 thin flat brownish or greenish bracts, broader erose appendages, 

 red-purple corolla, and the leaves more deeply dissected, more 

 arachnoid and scarcely at all tomentose. In reality C. coloradensis 

 is more closely related to C. scariosus, from which it differs mainly 

 in the less deeply dissected leaves and broader segments. 



Colorado : Pagosa Springs, 1899, Baker 6^^ (type) ; Gunni- 

 son, 1 90 1, Baker jg2 ; Wolcott, 1 902, Osterliout 26ji . 



