﻿612 Mackenzie: Notes on Carex 



a result at flowering time the flowerless culms are few in num- 

 ber, consisting only of the sterile shoots. While this difference 

 in manner of growth is very characteristic one must bear in 

 mind that any unusual spell of warm weather towards the end 

 of a season is apt to start into premature growth a shoot ready 

 for quick development the next year. When this happens the 

 result is the same biennial method of growth as in the boreal 

 plant. While this is not of very frequent occurrence, it makes 

 the use of this difference in habit of growth hardly useful as a key 

 character. 



For the group the Rocky Mountain plant under discussion 

 usually has stout culms and broad leaf-blades and presents a very 

 green general appearance. The closely allied Carex microptera 

 Mackenzie has narrower perigynia which are very narrowly 

 margined at base and have more spreading beaks giving the 

 head an echinate appearance lacking in the present species. 



Aven Nelson's No. 3275, collected July 2, 1897, in Albany 

 County, Wyoming, and in my herbarium, may be taken as the 

 type of C. festivella. A duplicate is in the New York Botanical 

 Garden herbarium. The species ranges from the Cypress Hills 

 in Saskatchewan and the Black Hills in North Dakota west to 

 eastern British Columbia and southward through the Rocky Moun- 

 tain region to Chihuahua, its best development being apparently 

 in Colorado and Wyoming where it is one of the most character- 

 istic mountain species. 



Specimens examined 



Canada: Between Keith and Columbia Rivers, J. Macoun 

 63304, Julys, 1902 (N. Y.); Banff, /. Macoun, July 12, 1891 (C); 

 Cypress Hills, Assiniboia, J. Macoun 7397, June 25, 1894 (C); 

 above Carbonate, Petersen 225, July 9, 1904 (N. Y.). 



South Dakota: Rochford, Black Hills, Rydberg 1087, July 12, 

 1892 (N. Y.); Custer County, Over 1768, June 20, 1914 (K. M.). 



Montana: Bozeman, Rydberg 3002, July 7, 1896 (N. Y.); 

 Little Belt Mountains, Flodman 305, August 10, 1896 (N. Y.) ; 

 Jocko Creek, MacDougal 280, June 16, 1911 (N. Y.) ; MacDougal's 

 Peak, MacDougal 601, July 10, 1901 (N. Y.); Spanish Basin, 

 Rydberg & Bessey 3798, June 28, 1897 (N. Y.); Aldridge, Mrs. 

 Scheuber no, 1901 (N. Y.); Elk Mountains, Rydberg 3017, 3289, 



