492 PROCEEDINGS OP THE AMERICAN ACADEMY. 



= = Spikclets remote, the uppermost strongly divaricate-pedunculate ; the lower- 

 most subtended by a long leaf-like bract : perigynia beaked. 



36. C. trisperma, Dewey. — Figs. 131, 132. — Culms almost fili- 

 form, 2 to 7 dm. long, usually much overtopping the soft narrow (0.5 to 

 2 mm. wide) leaves : the 2 or 3 spikelets, 2- to 5-Jlowered : the finely 

 many-nerved perigynia 3.3 to 3.8 mm. long, 1.6 to 1.8 mm. broad, 

 slightly exceeding the ovate-oblong pale obtuse to mucronate-acumiuate 

 scale. — Am. Jour. Sci. ix. 63, t. 3, fig. 12 ; Hook. Fl. Bor.-Am. ii. 213 ; 

 Schwein. & Torr. 1. c. 311 ; Carey, 1. c. 543 ; Boott, 1. c. i. 29, t. 74; 

 Bailey, Proc. Am. Acad. xxii. 144; Macoun, 1. c. 122; Britton, 1. c. 

 353, fig. 855; Howe, 1. c. 35. — Mossy woods and bogs, Newfound- 

 land and Labrador to Saskatchewan, south to northern Pennsyl- 

 vania, Ohio, Michigan, and Nebraska (according to Webber), and in 

 the mountains to Garrett Co., Maryland. Ascending to 770 m. in 

 the New England mountains. June-Aug. 



++ ++ Perigynia 1.2 to 1.5 mm. long, nerveless, with a very short broad truncate 

 beak, or beakless : culms wiry : spikelets 3 to 5, closely flowered, in a 

 greenish-brown or straw-colored linear spike. 



37. C elachycarpa. — - Figs. 133, 134. —Tufted, the stif slender 

 culms 3 or 4 dm. high, strongly scabrous above, longer than the soft 

 narrow (1 to 2 mm. broad) green leaves : spike 0.5 to 1.5 cm. long ; 

 the appressed ascending narrowly ovoid approximate or slightly remote 

 spikelets 3 to 6 mm. long : perigynia oblong, plump, smooth and nerveless, 

 subtruncate at base, shorter than the oblong-ovate acuminate dull-brown, 

 green-ribbed scales. — Maine, wet sandy river bank, Fort Fairfield, June 

 29, 1899 (31. P. Cook, E. L. Shaw & M. L. Fernald). A unique 

 plant, in maturity strongly suggesting an immature slender form of C. 

 echinata, or the little-known C. helvola, Blytt, which, however, have 

 very different perigynia. 



h- •*- Perigynia broadly elliptic to suborbicular : spikes mostly tinged with 



brown. 



++ Terminal spikelet with conspicuous clavate sterile base : perigynia rather 

 abruptly contracted to the slender beak. 



= Spikelets mostly distinct, the lowest 4 or 5 mm. thick. 



38. C. norvegica, Willd. — Figs. 135, 136. — Glaucous and/ree/y 

 stoloniferous ; culms smooth and soft, 1 to 4.5 dm. high, mostly over- 

 topping the soft flat rather narrow (1 to 2.5 mm. broad) leaves : spike 



