316 Rydberg: Studies on the Rocky Mountain flora 



Arenaria cephaloidea sp. nov. 



Somewhat cespitose perennial; stem strict, 2-4 dm. high, 

 glabrous; leaves glabrous, erect, filiform-subulate, 3-10 cm. long; 

 flowers in dense headlike cymes; bracts lanceolate, often I cm. 

 long, scarious except the thick midrib, scabrous-ciliolate; sepals 

 similar or somewhat broader, 4-5 mm. long; petals oblong, about 

 half longer than the sepals. 



This is related to A. congesta Nutt. but differs in its narrower 

 bracts, which are wholly scarious, except the midrib, and scabrous- 

 ciliolate on the margins; also in its larger flowers, stricter stem, 

 and less cespitose base. 



Washington: Spokane, Sept. 10, 1902, O. Kreager 617 (type, 

 in herb. N. Y. Bot. Garden); Clark Springs, July 17, 1902, 

 Kreager 100; Loon Lake, July 20, 1897, J- B. Winston; Spokane 

 County, June 27, 1884, Suksdorf. 



Idaho: Lake Coeur d'Alene, June and July 1892, G. B. Alton; 

 Little Potlatch River, June 2, 1892, Sandberg, MacDougal & Heller 

 478. 



Arenaria lithophila Rydb. comb. nov. 



Arenaria subcongesta lithophila Rydb. Mem. N. Y. Bot. Gard. 1: 



148. 1900. 



This, I think, deserves specific rank. Some of the specimens 

 recorded as A. subcongesta (S. Wats.) Rydb. should also be referred 

 to it. 



Alsinopsis dawsonensis (Britt.) Rydb. comb. nov. 



Arenaria daivsonensls Britt. Bull. N. Y. Bot. Gard. 2: 169. 1901. 

 This species has been collected in the Black Hills of South 

 Dakota. 



Alsinopsis pusilla (S. Wats.) Rydb. comb. nov. 



Arenaria pusilla S. Wats. Proc. Am. Acad. 17: 367. 1882. 

 This species has been collected in Idaho. 



Arenaria laxiflora nom. nov. 



Arenaria Fendlerl diffusa Porter, Syn. Fl. Colo. 13. 1874. Not 

 A. diffusa Ell. 1 818. 



