Vol. XXV, pp. 51-52 March 19, 1912 



PROCEEDINGS 



OF I'll i: 



BIOLOGICAL SOCIETY OF WASHINGTON 



A NEW CAREX FROM ALBERTA. 

 BY KENNETH K. MACKENZIE. 



[During the summer of 1911 Mr. X. Hollister and Mr. J. H. 



Riley, while engaged in field work in western Alberta and 

 eastern British Columbia, gathered, in addition to their collec- 

 tions of animals, a series of about two hundred characteristic 

 examples of the plant life of the region. Three of the higher 

 plants represented undescribed species, and diagnoses of them 

 have recently been published.* The representatives of the 

 difficult genus Carex were forwarded to Mr. Kenneth K. Mac- 

 kenzie of New York City, who has been engaged in the prepara- 

 tion of a monograph of the North American species. While 

 only three species are represented in the collection they are of 

 unusual interest, since one appears to be undescribed and 

 another has rarely been collected. A diagnosis of the new 

 species, prepared by Mr. Mackenzie, is published here at his 

 suggestion. — Paid C. Standley.^\ 



Carex atrosquama Mackenzie, sp. nov. 



Culms in dense clumps, .'50 to 45 cm. high, phyllopodic, slender, erect 

 or the apex nodding at maturity, sharply triangular, slightly roughened 

 toward the apex, much exceeding the leaves, purplish-brown tinged and 

 slightly fibrillose at base; leaves with well-developed blades seven to ten 

 t<> a fertile culm, inserted on the lower fourth, mostly clustered near the 

 hase, tin' Mades deep green, fiat with slightly revolute margins, 2.5 to 

 3.5 mm. wide, 10 to 20 cm. long, roughened toward the apex; opaque 

 part of sheaths whitish or yellowish -white ; spikes three or four, approxi- 

 mate or the lower slightly separated, the lower one or two on erect 

 peduncles half to twice their length, the others sessile or nearly so, oblong, 

 6 to L2 mm. long, 5 mm. wide, densely 15 to 30-flowered, the appressed 

 perigynia in several ranks, the lateral spikes pistillate, the terminal 

 •Smith-. Mix-. Coll. 56 : No. :::). 



8— Proc. Biol. Soc. Wash., Vol. XXV, 1912. (51) 



