(320) 



4. Scirpus L. Bulrush. 



Spikelets ^ , oo-flowered. Palets imbricate 

 all round, the lowermost empty. Perigonium 

 6-setaceoiis. Style articulate with its base. 



1. S. LACUSTKis L. Inflorescence apparent- 

 ly lateral, with a single erect involucral leaf; 

 stem almost terete; bristles of perigonium 6, 

 slender, with scattered barbs — 21- Common. 

 Summer. 



2. S. Tatoka Kunth. Inflorescence appar- 

 ently lateral, with a single erect involucral leaf; 

 stem almost terete; bristles of perigonium less 

 than 6, stout and retrorsely plumose. — 71. Be- 

 nicia. Summer. 



3. S. Olneyi Gray. Inflorescence appar- 

 ently lateral, with a single erect involucral leaf; 

 stem triquetrous. — It- Presidio. Summer. 



4. S. MARITIMUS L. Involucre spreading; 

 spikelets large in a sessile cluster or sparingly 

 umbellate. — U- Common. Summer. 



5. S. SYLVATicus L. Involucre spreading; 

 spikelets small in a supra-decompound inflores- 

 cence. — 71- Common. Summer. 



6. S. ACicuLARis L. (EleocJiaris R. Br.). 

 Spike distichous or 3-ranked, few-flowered, 

 terminating a leafless stem. — 0. Common. 

 Spring. 



7. S. PALUSTRis Reichenb. (EleocJiaris R. 

 Br.). Spike terete, co-flowered, terminating a 

 leafless stem. — 71. Common. Summer. 



