﻿618 Mackenzie: Notes on Carex 



Specimens examined 

 Texas: Dallas, Reverchon 2422, April 13, 1901 (K. M.); also 

 241P, March 26, 1901 (K. M.); also 2423, May 2, 1901 (K. M.); 

 also 2416A, April 16, 1901 (N. Y., K. M.); Fort Worth, Ruth 360, 

 April 12, 1913 (type in Herb. K. M.); Tarrant County, Ruth 

 4SI, April 4, 1914 (K. M.); Austin, Rugel (C). 



Carex onusta sp. nov. 



Cespitose from short, fibrillose rootstocks, the culms aphyl- 

 lopodic, 2-3.5 dm. high, stiff, but rather slender, bluntly triangular 

 below, sharply triangular and roughened above, exceeding leaves, 

 brownish at base. Leaves with well-developed blades three or four 

 to a fertile culm, the sheaths tight, inconspicuously septate nodu- 

 lose, cross rugulose ventrally and thickened at mouth, the blades 

 green, flat, 2.5-3.5 mm. wide, mostly 1-2 dm. long. Head oblong 

 or oblong-ovoid, dense, 8-13 mm. wide, 1.5-3 cm. long, containing 

 eight to fifteen androgynous spikes, the lower only readily dis- 

 tinguishable. Lower bracts setaceous, shorter than head, the 

 upper scale-hke. Spikes with five to fifteen appressed or at 

 length spreading or ascending perigynia, the apical staminate 

 flowers usually forming a conspicuous but short cone. Scales 

 ovate, cuspidate, hyaline, yellowish-brown tinged with green mid- 

 vein, narrower than and about two thirds length of body of 

 perigynia. Perigynia plano-convex, or slightly bi-convex, 3 mm. 

 long, 1.5 mm. wide, oblong-ovate, green or in age yellowish, 

 nerveless ventrally, obscurely few-nerved dorsally, sharply mar- 

 gined to the rounded non-spongy base, abruptly beaked, the beaked 

 0.75 mm. long, bidentate, serrulate. Achene plano-convex, filling 

 perigynia 2.5 mm. long, 1.4 mm. wide, minutely truncately apicu- 

 late, the style short with much enlarged base. Stigmas two. 



The perigynia strongly resemble those of Carex Leavenworthii 

 Dewey and the scales are short, as in that species. The heads, 

 however, are elongated, as in Carex Muhlenbergii Schk. The 

 thin yellowish-brown tinged scales are peculiar and characteristic. 



The type, collected by Professor Albert Ruth, No. 458, on 

 April 24, 1914, in sandy woods in Tarrant County, Texas, is in 

 my herbarium. These specimens are in most excellent condition. 



Carex Sheldonii n. sp. 

 Tufted, strongly stoloniferous, the stolons stout. Culms 

 phyllopodic, 7.5 dm. high, glabrous, obtusely angled and very 

 smooth below inflorescence, exceeding the elongated leaves, 



