82 



CYPERACEAE. 



Stems setaceous; spikelet 1 to 3 lines long; style 3-cleft; achene obscurely triangular or 



almost obovoid 1. II. acicularis. 



Sitins stout ish; spikelet 3 to 12 lines long; style 2-cleft; achene plano-convex 



2. E. palustris. 



1. E. acicularis B. Br. Slender Spike-rush. Eootstock very slender, 

 creeping; stents I to 8 in. high, very slender; spikelet 1 to 3 lines long, few- 

 flowered; bractlets ovate-oblong, 1% lines long, reddish brown with broad green 

 mid-vein; style deeply 3-cleft; achene Vi> line long, obscurely triangular, ribbed 

 on the sides; tubercle broad, short and blunt. 



Moist places: San Francisco. Aug. 



2. E. palustris R. Br. Common Spike-rush. Perennial; rootstock stout, 

 creeping, stoloniferous; stems y 2 to 2 ft. high, slender, mostly terete, sheathed 

 at the base, leafless; sheaths sub-truncate; spikelet many-flowered, 6 to 12 

 lines long, oblong-lanceolate to linear, brown with broad whitish margin and 

 greenish keel; style 2-cleft; achene plano-convex, rounded but not at all angled 

 on the back, 1 line long including the tubercle, which is constricted at the 

 point of junction. 



Common in marshes and shallow, slow-moving creeks: Glen Ellen; San 

 Francisco; Lake San Andreas; Stege. May- June. 



3. FIMBRISTYLIS Vahl. 

 Annuals or perennials. Stems leafy below. Spikelets umbellate or capitate, 

 terete, subtended by a 1 to many-leaved involucre. Stamens 1 to 3. Bristles 

 none. Style 2 to 3-cleft its base much swollen, the whole falling away from the 

 achene at maturity. Achene lenticular or triangular. (Latin fimbri, thread- 

 like, stylus, style.) 



Spikelets umbellate, solitary 1. F. miliacca. 



Spikelets clustered 2. F. apits. 



1. F. miliacea Vahl. Annual (?); umbel diffusely compound; spikelets 

 sub-globose, about 1 line long; style 3-cleft; achene acutely triangular, muri- 

 cate-tuberculate. 



Reported as introduced at San Francisco. 



2. F. apus (Gray) Wats. Annual; spikelets in 'nearly sessile clusters, lance- 

 olate, 2 lines long; style 2-cleft; achene lenticular, obovate, faintly tuber- 

 c ul ate. 



Clear Lake, Bolander. 



4. SCIRPUS L. Club-rush. Bulrush. 

 Annuals or perennials. Stems leafy or the leaves reduced to mere sheaths 

 at base. Spikelets terete or somewhat flattened, solitary or in heads, spikes or 

 umbels, subtended by an involucre or 1 to several Leaves or the involucre obso- 

 lete. Bristles 3 to 6, barbed, ciliate, or obsolete. Stamens 2 to 3. Style 2 

 to 3-cleft, not swollen at the base, deciduous or its base persist ettt on the 

 achene. Achene triangular, lenticular or obovoid. (Latin scirpus, bulrush.) 



Stems low and slender; inflorescence terminal; spikelet mostly solitary; bristles obsolete. — 

 Sub-genus [solepis Benth. 



Stems 2 to 6 in. high; bractlets obtuse or mucronate: involucral bract 1 to .1 lines long.. 



1. .V. riparius. 



Stems 1 to 3 in. high; Inaetlets acute, shortlj beaked, strongly keeled; involucral hraet 



5 to 9 lines long -'. .V. carinatus. 



Stems tall and stout; spikelets in clusters, umbels or panicles; I>ri>t1cs retrorscly barbed 



ciliate or rarely obsolete. Sub-genus Euscirpus Benth. 



[nflorescence apparently lateral: involucre of a single erect bract. 



Stem terete or nearly so. leafless or nearly so; spikelets umbellate 3. 5. laCHStris. 



