184 Rydberg : Studies on Rocky Mountain Flora 



leaves mostly small, pinnately divided into short oblong segments : 

 heads 2-3, about 6 mm. high, somewhat turbinate ; bracts 12-15, 

 broadly lanceolate, conspicuously membraneous margined : rays 

 none : achene glabrous. 



The species is named from the resemblance the basal leaves 

 have to those of certain species of Valerianella which genus has 

 also been known under the name Fedia. [Plate 5, f. 7.] 



Colorado : South Park, 1871, W. M. Canby (type in the her- 

 barium of the College of Pharmacy, New York). 



SUBNUDI 



A 



rootstock, 



perfectly glabrous, sparingly leafy, monocephalous : basal leaves 

 broadly obovate, coarsely crenate-dentate : heads decidedly turbi- 

 nate with narrow linear-acuminate bracts; calyculate bracts, if 

 present, few, and half as long as the main series. A single species. 



24. Senecio subnudus DC. Prod., 7 : 428. 1837 



Senecio aureus var. subnudus Gray, Syn. Fl. I 2 : 391. 1884. 



This species has been included as a variety of S. aureus, but I 

 think it should be regarded as the type of a distinct group. The 

 long slender horizontal rootstock and the decidedly turbinate in- 

 volucre is not found in any of the aureus allies. The latter char- 

 acters would place it near S.frigidus. [Plate 6, f. 2.] 



Washington: Chiquash Mountains, 1892, Suksdorf, 2167; 

 Cascade Mountains, 1882, Brandcgee, 118. 



Oregon: 1882, T Howell ; 1871, Elihu Hall, j 04. 



California: Butterfly Valley, 1874, Mrs. R. M. Austin. 



Montana: Park Co., 1887, Tweedy ,344; Pony, 1897, Ryd- 

 berg & Bessey, 5270. 



Wyoming: Wind River, 1842, Fremont; Buffalo Fork, 1897, 

 Tweedy, 587 ; Yellowstone Park, 1884, Tweedy, 120. 



TOMENTOSI 



Perennials, over 2 dm. high, with a short caudex or root- 

 stock, which often is subligneous and cespitose, floccose when 

 young, becoming more glabrate in age, but with some wool 

 always remaining : basal leaves, except the very first ones, from 

 serrate or dentate to pinnatifid : stem leaves always present, but 

 often reduced, generally pinnatifid or pinnately lobed or toothed : 

 heads cymose, small, with few and very small calyculate bracts. 



