1	Spikes unisexual and bisexual, uppermost 1 or 2 spikes androgynous or gynaecandrous, remaining spikes female, or uppermost 1 or 2 spikes male and remaining female or bisexual		(2)
+	Spikes usually unisexual, uppermost 1 or 2 spikes male (C. planiculmis sometimes bearing male spikes with several female flowers at top), remaining spikes female, sometimes with few male flowers at top (e.g., C. doniana)		(6)
2 (1)	Uppermost 1 or 2 spikes bisexual, androgynous or gynaecandrous, remaining spikes female, spikes oblong, not over 2 cm, approximate, usually congregate at top of culm; female glumes stramineous or yellowish green		(3)
+	Uppermost 1 or 2 spikes male, remaining spikes female or bisexual, bisexual spikes androgynous or gynaecandrous, spikes cylindric, 2.5-10 cm, remote, not congregate at top of culm; female glumes purple or brown-red		(4)
3 (2)	Spikes 2, rarely 3, androgynous, with few male flowers at top of spike; female glumes lanceolate, ca. 2 mm; utricles ca. 3 mm; nutlets stipitate.		271 C. harrysmithii
+	Spikes 3 or 4, rarely 2, terminal spike gynaecandrous, lateral spikes female; female glumes ovate, ca. 3 mm; utricles 3.5-4 mm; nutlets sessile.		272 C. agglomerata
4 (2)	Rhizome stoloniferous; leaves glabrous; female spikes densely many flowered, usually with few male flowers at base; female glumes muticous or mucronate; utricles with a short beak.		273 C. alliiformis
+	Rhizome without stolons; leaves pubescent abaxially; female spikes laxly flowered, usually with few male flowers at top; female glumes long aristate or awned; utricles with a long beak		(5)
5 (4)	Leaves 7-12 mm wide; male spike 7-10 cm; utricles spreading.		274 C. purpureotincta
+	Leaves up to 17 mm wide; male spike 4-6 cm; utricles reflexed.		275 C. xiangxiensis
6 (1)	Utricles wholly scabrid pubescent.		282 C. scabrisacca
+	Utricles glabrous, not scabrid		(7)
7 (6)	Spikes approximate, usually congregate at top of culm, male spikes clavate, 1.5-2 cm, female spikes oblong, not over 2.5 cm (only C. huashanica with male spikes 2-5 cm, female spikes 3-6 cm), subsessile or shortly pedunculate		(8)
+	Spikes remote, not congregate at top of culm, male spike and female spikes cylindric (C. japonica with spikes oblong), 2.5-7 cm, lower spikes long pedunculate, upper spikes shortly pedunculate		(12)
8 (7)	Female spikes cylindric, 3-6 cm; female glumes with long awn at apex, scabrous on margins at awn; utricles ca. 5 mm, obliquely truncate or emarginate at orifice.		276 C. huashanica
+	Female spikes oblong, not over 2.5 cm; female glumes muticous or mucronate; utricles 3-4 mm, 2-toothed at orifice (except in C. submollicula)		(9)
9 (8)	Leaf blades 2-4 mm wide; utricles ca. 5 mm, distinctly veined.		280 C. submollicula
+	Leaf blades 4-10 mm wide; utricles 3-4 mm, obscurely veined		(10)
10 (9)	Female spikes 1.5-2.5 cm; utricles oblong-ovate, slightly inflated trigonous, membranous, usually rugulose, apex abruptly contracted into a medium-sized to long beak.		279 C. mollicula
+	Female spikes 0.8-1.7 cm; utricles elliptic, inflated trigonous, thickly papery, smooth, apex abruptly contracted into a short beak		(11)
11 (10)	Female glumes ovate or narrowly ovate; nutlets obovate.		277 C. aphanolepis
+	Female glumes oblong; nutlets subrhomboid.		278 C. radicina
12 (7)	Leaf blades 5-12 mm wide; female spikes (1.5-)2-7 cm; utricles attenuate to a short beak at apex, nearly obliquely truncate or obscurely 2-toothed at orifice		(13)
+	Leaf blades 2-5 mm wide; female spikes 1-3(-4) cm; utricles attenuate to medium-sized or long beak at apex, distinctly 2-toothed at orifice		(15)
13 (12)	Culms compressed triquetrous, one angle obscure; male spike not over 3.5 cm, with female flowers at top, female spikes 1.5-4.5 cm, without male flowers at top; female glumes ovate, muticous or sometimes mucronate at apex; utricles ovate, with a recurved beak, style deciduous, stigmas short.		288 C. planiculmis
+	Culms triquetrous; male spike 3-7.5 cm, female spikes 2-7 cm, sometimes with several male flowers; female glumes ovate-lanceolate, mucronate at apex; utricles oblong-ovate, with a straight beak; style usually persistent, stigmas rather long		(14)
14 (13)	Spikes 2-6, male spike linear-cylindric, 3-7.5 cm, female spikes cylindric, 3-7 cm; female glumes pale yellow; utricles 3.5-4 mm, greenish yellow; basal leaf sheaths brownish.		286 C. doniana
+	Spikes 3 or 4, male spike narrowly cylindric, ca. 3 cm, female spikes cylindric, 2-3.5 cm; female glumes yellow-brown; utricles 4-4.5 mm, olivaceous; basal leaf sheaths purple-brown.		287 C. phaenocarpa
15 (12)	Female spikes oblong or oblong-cylindric, 1-2.5 cm; utricles 4-5 mm, stramineous, slightly nitid, obscurely veined.		281 C. japonica
+	Female spikes cylindric, to 3 cm or more; utricles ca. 3.5 mm, yellowish green, not nitid, distinctly veined		(16)
16 (15)	Culms 30-60 cm tall; male spike clavate, 2-3 cm; female glumes narrowly ovate, muticous at apex; utricles ovate, slightly inflated.		285 C. alopecuroides
+	Culms not over 30 cm tall; male spike linear, 1-5 cm; female glumes oblong-ovate, mucronate at apex; utricles elliptic or oblong, not inflated		(17)
17 (16)	Utricles elliptic, 3-3.5 mm, with a medium-sized to long beak, beak ca. 1/3 length of utricle.		283 C. subtransversa
+	Utricles oblong, 4-5 mm, with a long beak, beak ca. 1/2 length of utricle.		284 C. liui