98 CYPERACEAE (SEDGE FAMILY) 



with broad obtuse scales: perigynium short, nerveless, with entire beak, ex- 

 ceeding the scale. In the higher Rocky Mountains of British America and 

 extending south into Wyoming. 



28. Carex acutina Bailey, Mem. Torr. Bot. Club 1: 52. 1889. Stems erect, 

 4-5 dm. high, smooth or rough above, leaves flat and thin, about as long as the 

 stem: the lower 1 or 2 bracts flat and leaf-like, about equaling the stem, the 

 margins mostly serrate: spikes 4-5, the upper 1 or 2 staminate, all approxi- 

 mate and sessile or the lower short-peduncled, 3-5 cm. long: perigynia thin 

 and soft, yellowish, somewhat inflated, the small beak entire, shorter, or 

 longer and broader than the obtuse or muticous scale. [C. rhomboidea Holm, 

 Am. Journ. Sci. 16: 35. 1903 (?).] On stream banks and lake shores; Colo- 

 rado to Oregon. 



29. Carex variabilis Bailey, Mem. Torr. Bot. Club 1: 18. 1889. Glaucous, 

 mostly low, 3-5 dm. high, stout: culm sharply angled, roughish on the angles: 

 leaves rather broad: spikes 3-4, short and stout, borne near the top of the 

 culm, erect, the lower one or two conspicuously attenuated at the base, and 

 appearing clavate; the upper sessile, lower peduncled: bracts leaf-like and 

 broad, the lower one or two equaling or exceeding the culm: perigynium small 

 and broadly ovate, abruptly and very shortly beaked, nerveless, beak entire, 

 green or whitish, conspicuously broader and usually shorter than the obtuse 

 or muticous black scale. C. aperta divaricata. Wet places; Colorado to 

 Montana and Idaho. 



M- -M- Culms 1-4 dm. high: leaves more or less involute when dry. 



30. Carex Bigelovii Torr. Ann. Lye. N. Y. 1 : 67. 1824. Culms mostly stout, 

 sharp-angled, smooth except near the top, longer than the narrow leaves: 

 staminate spike one : pistillate spikes 3-5, slender, lax, loosely flowered at the 

 base, the lower peduncled and often remote, black-purple or fuscous-purple: 

 perigynium narrow, mostly elliptic, almost pointless, entire at the orifice, very 

 faintly nerved towards the base, shorter or rarely a little longer than the acute 

 or acutish dark purple scale. C. vulgaris hyperborea. Alpine regions; Colo- 

 rado, northward and westward. 



31. Carex rigida Gooden. Linn. Trans. 2: 193. 1794. Leaves 4 mm. broad, 

 flat: staminate spikes sometimes 2, usually 1: pistillate spikes 3-5, short and 

 thick, 5-20 mm. long, erect, approximate or the lowest sometimes remote and 

 shortly peduncled, dark purple; auricles very prominent: perigynium obovate 

 or nearly circular, nerveless, shortly beaked, pale below, usually more or less 

 purple above, commonly shorter than the dark, acute scale. C. vulgaris 

 alpina. Same range as the last. 



32. Carex scopulorum Holm. 1. c. Plant rather stout, from a dense and 

 woody root, 3-6 dm. high: leaves very broad for the group, deep green, con- 

 spicuously pointed, shorter than the culm: staminate spike usually 1, mostly 

 short-peduncled: pistillate spikes 2-4, sometimes contiguous or partially 

 scattered, oval or oblong, 1-4 cm. long, the two lowest usually on slender 

 peduncles 3-5 cm. long, the others sessile or nearly so: lowest bract leaf-like 

 and equaling or exceeding the culm: perigynium compressed-trigonous, ovate 

 or round-ovate in outline, pale and more or less discolored or even covered 

 with purple dots (or rarely almost yellow), produced into a very short and 

 entire beak, mostly shorter than the obtuse or muticous purple scale: stigmas 

 2 or 3. C. vulgaris in part. (C. Tolmiei and vars.) Colorado to Montana and 

 west to the coast States. 



11. Staminate spike one, short, either pistillate above or not conspicuous 

 (except in No. 33): pistillate spikes none to several, short and thick, mostly 

 dark-colored, commonly aggregated (often only approximate}, sometimes stam- 

 inate at the base: perigynium biconvex or very obtusely 3-angled, with a very 

 xhurt entire or emarginate beak, or beakless: stigmas 2 or 3. MELANOSTACH- 

 YAE Turkin. Mostly mountain or boreal species, distinguished by the 

 aggregated spikes and inconspicuous or androgynous terminal spike and 

 nigrescent color. 



