210 CYPERACEAE 



Lower eulni sheaths strongly yellowish-brown tinged, sharply keeled; culms stout, the leaf- 

 blades 6 to 12 mm. wide _ 109. C. scliottii. 



Lower culm sheaths purplisli-tinged, not sharply keeled; culms more slender, the leaf -blades 

 narrower 110. C. scnta. 



B. Some ob all of the rLowERiNG culms arising laterally axd not envei-oped at base 



BY previous year's TUFT OF LEAVES. 

 Culms very densely cespitose, forming dense stools; lowest sheaths strongly tilamentose; lowest 



bract little developed, usually much exceeded by inflorescence 111. C. nudata. 



Culm much less densely cespitose, forming beds, conspicuously stoloniferous; lowest bract well- 

 developed, from somewhat shorter than to exceeding inflorescence. 



Perigynia orbicular or nearly so 112. C. eurycarpa. 



Perigynia oblauceolate 113. C. oxycarpa. 



29. Cryptocarpae. 

 Perigynia dull, straw-colored or light brown, slightly granular; lower sheaths of sterile shoots 



not iilanieutose 114. C. lyngbyei. 



Perigynia shining, brown, smooth; lower sheaths of sterile shoots strongly filamentose 



115. C. obnupta. 

 30. Trachychlaenae. 



Eepreseuted by one species in our range 116. C. spissa. 



31. Hirtae. 

 Beak of perigynimn obliquely cut, shallowly bidentate at matiu'ity; foliage pubescent; stam- 



inate scales long-eiliate 117. C. yosemitana. 



Beak of perigjuium deeply bidentate; staminate scales at most erose. 

 Poliage not pubescent ; teeth of perigynium beak .short. 



Lowest bract strongly sheathing; fertile culms phyllopodic with many leaves, the sheaths 



not breaking and becoming filamentose _ 118. C. oregonensis. 



Lowest bract not sheathing; fertile culms aphyllopodie mth few leaves, the sheaths 



breaking and becoming filamentose 119. C. lanuginosa. 



Sheaths and under surface of leaf-blades hairy; teeth of perigynium beak conspicuous 



120. C. sheldonii. 

 32. Extensae. 



Represented by one species in our range 121. C. viridula. 



33. Physocarpae. 

 Perigynia ascending; lower sheaths more or less strongly filamentose; culms sharply triangular. 



Perigynia 4 to 8 mm. long, abruptly contracted into beak 122. C. vcsicaria. 



Perigynia 7 to 10 mm. long, tapering into beak. 123. C eisiecata. 



Perigynia spreading at niaturitj'; lower shc3,ths not filamentose; culms bluntly triangular below 



spikes _ 124. C. rostrata. 



34. Pseudo-Cypereae. 

 Perigynia suborbicular in cross-section, more or less inflated; teeth of perigynium beak 0.5 to 



1 mm. long _ 125. C. hystricina. 



Perigynia obtusely triangular, scarcely inflated, closely enveloping achene; teeth of perigynium 

 beak 1.5 to 2 mm. long, recurved or spreading 126. C. comosa. 



Sect. 1. Inflatae Kiik. Cespitose, the rootstocks elongate. Leaf-blades filiform. Spike soli- 

 tary, ovoid, androgynous, densely flowered, bractless. PerigjTiia inflated, the walls very 

 thin, slightly nerved, sessile, the smooth Ijeak hyaline-tipped, obliquely cut, in age bidentu- 

 late. Achenes triangular. Stigmas 3. 



1. C. engelmannii Bailey. Culms 5 to 20 cm. high; spike 10 to 15 mm. long, 

 6 to 10 mm. wide, the lower % pistillate ; scales acute to cuspidate, all except 

 lower shorter tliau perigynia; perigynia 4.5 to 5 mm. long, 2.25 mm. wide. 



Alpine peaks or meadows, Sierra Nevada in Tulare Co. North to Wa.shing- 

 ton, east to Colorado. 



Locs. — Kaweah Peaks, Dudley 2215 ; Chagoopa Mdws., Dudley 2272. 



Ref. — Carex engelmannu Bailey, Proc. Am. Acad. 22:132 (1886), type coll. by EngeJmann, 

 probably near Colorado Sprs., Colo. 



2. C. breweri Boott. (Fig. 28.) Culm.s 1 to 2.5 dm. high; spike 1 to 2 cm. 

 long, 6 to 10 mm. wide, the upper third staminate; scales ovate, short-acuminate, 

 narrower and shorter than perigynia; perigynia 5 mm. long, 3.5 mm. wide. 



High alpine peaks of the Sien-a Nevada from I\It. Whitney to Mt. Shasta. 

 North to "Washington. 



Locs. — Mt. Whitney, Jepson 1085; head of San Joaquin River, Brciver 2831; Mt. Dana, 

 Brewer 1863 ; Mt. Shasta, Jepson. 



Refs. — Carex breweri Boott, 111. Carex 4:142, pi. 455 (1867), type loc. Mt. Shasta, Brewer 

 1422; Mackenzie, Erythea 8:18, fig. 1 (1922); Kiik. in Engler, Pflzr. 4=":96, fig. 20h-k (1909). 



