15 



Beak of perigynium shallowly bidentate, the teeth Httle 



whitish C. vesperlina. 



Mature perigynia 1.5 mm. wide, the body round-triangular in 



cross-section C. pennsylvanica. 



Carex heliophila n. sp. 



In small to medium-sized clumps, from slender, more or less 

 elongated rootstocks, stoloniferous but the stolons less conspic- 

 cuous than in C. pennsylvanica Lam.; culms 12-25 cm. high, 

 phyllopodic, reddish-brown and often strongly fibrillose at base, 

 exceeding all or most of the leaves, slender but stiff, wiry and 

 erect, rough on the angles above. Leaves with well-developed 

 blades 5-10 to a fertile culm, the blades flat with slightly revolute 

 margins, 1-2 mm. wide, 4-20 cm. long, much roughened, the 

 lower sheaths frequently breaking and becoming filamentose; 

 terminal spike staminate or occasionally with a few perigynia 

 towards apex, 8-20 mm. long, 3-6 mm. wide, more or less pe- 

 duncled, many flowered, the scales ovate, obtusish to acute or 

 short cuspidate, reddish-brown with lighter mid-veins and con- 

 spicuous white hyaline margins; pistillate spikes one or two or 

 rarely three, from contiguous to more or less strongly separate, 

 globular, and sessile or nearly so, 4-6 mm. long, closely 5-15- 

 flowered in several ranks, the perigynia ascending; bracts not 

 sheathing, scale-like, or occasionally green and prolonged, but 

 shorter than inflorescence; scales ovate, acute, or short cuspidate, 

 varying from obtusish to strongly cuspidate, reddish-brown with 

 1-3-nerved lighter center and white hyaline sides (but scarcely 

 apex), from slightly longer to slightly shorter than, but not 

 enveloping or concealing perigynia; perigynia puberulent, dull 

 green, 3.5 mm. long, the body short oval, 2.25 mm. long, 2 mm. 

 wide, 2-ribbed, otherwise nerveless, globose in cross section, 

 strongly stipitate (0.5 mm. long.), abruptly contracted into the 

 serrulate strongly bidentate beak, 0.75 mm. long, the teeth 

 slender, readily breaking, strongly whitish; achenes triangular 

 with strongly convex sides, closely enveloped by perigynia, 

 2 mm. long, 1.75 mm. wide, truncate, round-tapering at base; 

 style slender, scarcely enlarged at base, readily detached; stigmas 

 three. 



Of the numerous specimens of this species examined, I designate 

 a specimen collected on the open prairie, near Lee's Summit, 

 Jackson County, Missouri, on May 9, 1897, now in my own 

 herbarium, as the type. 



