[Vol. 9 

 144 ANNALS OF THE MISSOURI BOTANICAL GARDEN 



480 p, in diameter, obscurely or more distinctly marked with low 

 tubercles or wrinkles ; microspores 23-30 n long, more or less 

 spinulose. 



Distribution: Idaho, Wyoming, Colorado, Utah, Arizona, Bri- 

 tish Columbia, Washington, Oregon, California. 



Specimens examined: 



Idaho: Bitter Root Forest Reserve, alt. 2050 m., 26 August, 

 1897, Leiberg 39 (Mo. Bot. Gard. Herb.); head of Bear 

 Creek, Bitter Root Forest Reserve, alt. 2050 m., 26 August, 

 1897, Leiberg 2939 (U. S. Nat. Herb.). 



Wyoming: shallow pond near falls of Yellowstone River, 187o, 

 Parry 307 (Mo. Bot. Gard. Herb., N. Y. Bot. Gard. Herb., 

 and Gray Herb.) ; Yellowstone Park, June, September, 1885, 

 Tweedy 417 (U. S. Nat. Herb.); ponds, Snake River, 9000 

 ft., August, 1897, Tweedy 362 (N. Y. Bot. Gard. Herb.); 

 Yellowstone Lake, 12 August, 1897, Rydberg & E. A. Bessey 

 3520 (U. S. Nat. Herb., N. Y. Bot. Gard. Herb., and Gray 

 Herb.) ; Yellowstone Park, 4 August, 1902, M earns 2807 (U. 

 S. Nat. Herb.); entirely submerged in shallow pond cut off 

 from north end of Yellowstone Lake, 16 August, 1900, C. E. 

 Bessey 2 (N. Y. Bot. Gard. Herb.). 



Colorado: ponds in Elk Mts., 1881, Brandegee 2001 (Mo. Bot. 

 Gard. Herb.) ; lake in Gunnison River Valley, 10,000 ft. alt., 

 lakes near timber line, main range, Routt Co., September, 

 1891, Trelease (Mo. Bot. Gard. Herb.); (probably) sub- 

 merged on coarse granite bottom, Ward, Boulder Co., alt. 

 2500 m., Clokey (Schmoll) 3986 (Mo. Bot. Gard. Herb.). 



Utah: subalpine lake, Alta, Wasatch Mts., 12 August, 1879, 

 Jones (Mo. Bot. Gard. Herb, and U. S. Nat. Herb.) ; Alta, 

 Wasatch Mts., August, 1883, Jones (N. Y. Bot. Gard. Herb.). 



Arizona : in a lake about 2 miles east of Tunnel Road, Black Mess, 

 Forest Reserve, 1 June, 1900, Coville 1053 (U. S. Nat, 

 Herb.). 



British Columbia : Indian Reservation, Kamloops, 29 June, 1889, 

 John Macoun 1^212 (Gray Herb.) ; in 6 feet of water, Lake 

 Mara, Sicamous, 7 July, 1889, J. Macoun (N. Y. Bot. Gard. 

 Herb.). 



Washington: ponds, alt. 6300 ft., Cascade Mts., August, 1882, 

 Tweedy (Mo. Bot. Gard. Herb, and N. Y. Bot. Gard. Herb.) ; 



