21 RvDBERG : Studies on the Rocky Mountain Flora 



margined, densely villous-tomentose : flowers heterogamous, but 

 all fertile, light yellow : receptacle glabrous. 



This species belongs to the A. Ludovici(xna 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. 

 Ludoviciaiia 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. diver sifolia grows on sandy beaches up 

 to an altitude of 2200 m. 



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

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

 Dougal & Heller, jog. 



Washington: 1889, G. R. Vasey, ^yg. 



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



6603. 



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 i 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 i 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. biehins (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 &- 

 Vreeland, 54.^5. 



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 



