Rydberg : Studies on the Rocky Mountain Flora 21 



margined, densely villous-tomentose : flowers heterogamous, but 

 all fertile, light yellow : receptacle glabrous. 



This species belongs to the A. Ludoviciana group, and in many 



respects agrees with the original description thereof. It is, how- 



ever, a western species, not growing near the region from which A. 



Ludoviciana was described. What the latter really is I have been 



unable to settle. The one that I think is the only one that has 



any claim for the name, is a lower plant from Missouri to Colorado, 



/ 



with shorter leaves, more green above, with more divergent lobes 

 and brownish flowers. A. diversifolia grows on sandy beaches up 

 to an altitude of 2200 m. * 



Idaho: Priest River, 1900, D. T. MacDongal, igo (type); 

 Farmington Landing, Lake Coeur d'Alene, 1892, Sandberg, Mac- 

 Doit gal & Heller , 5 op. 



Washington: 1889, &. R. Vasey, ^yp. 



Wyoming: Yellowstone Lake, 1899, Aven & Elias Nelson, 



66oj. 



^ Picradenia helenioides sp. nov. 



\ 



A comparatively tall, finely pubescent plant with apparently 

 only biennial root Stem leafy, about 5 dm. high, with several to 

 many erect branches : leaves rather firm, distinctly ribbed, finely 

 pubescent ; the lower petioled and with half clasping bases : 

 basal leaves entire, very narrowly linear-oblanceolate ; middle 

 stem-leaves erect, fully 1 dm. long, parted into 3-5 linear divi- 

 sions : upper stem-leaves linear, entire : heads corymbose : invo- 

 lucre somewhat tomentose, 8-10 mm. high and often 15 mm. 

 broad ; outer bracts united only at the base, lanceolate, longer 

 than the inner, 14-18 in number: rays orange, about 1 cm. long, 

 2-3 mm. wide, 3-toothed at the apex: achenes silky: scales of 

 the pappus broadly lanceolate, acuminate. 



It is nearest related to P. biennis (A. Gray) Greene ; but differs 

 in the yellowish green herbage, the erect branches, the broader 

 segments of the leaves and the darker flowers. It grows in moun- 

 tain valleys at an altitude of about 2700 m. 



Colorado: On Sangre de Christo Creek, 1900, Rydberg & 



Vr eel and, 5495. 



^Antennaria Piperi sp. nov. 



Somewhat surculose-rosuliferous : basal leaves 2-4 cm. long, 

 obovate or oval with a short petiole, densely floccose on the lower 

 surface, only slightly so on the upper surface when young, but 



