I'll. JUNCACEAE 287 



8. Inflorescence distinctly secund; dry soil, rare; Jack- 

 son, Pope, and Saline counties-.-./, secundus Beauv. 



8. Inflorescence not secund. 



9. Auricles at the summit of the sheaths thin, 

 scarious, hyaline, conspicuously pi'olonged 1-3 

 mm beyond the point of insertion; fields, 

 roadsides, j^aths, open woods, very common. 

 May-Sept. Path Rush /. tenuis Willd. 



9. Auricles firm, not conspicuously prolonged be- 

 yond the point of insertion. 

 10. Sheaths and amides membranous, hyaline; 

 perianth appressed to the capsule, 3-4 mm 



long; sandy soil, common. May- Aug 



-- /. interior Wieg. 



10. Sheaths and auricles cartilaginous, yellowish, 

 rigid, glossy; perianth somewhat divergent, 

 4-5 nmi long; meadows, common. May- 

 Aug - /. dudleyi Wieg. 



4. Flowers in heads (glomerules) . 



11. Heads few (2-20), commonly 5- to 10-flowered; stamens 

 not persistent ; meadows or ditches, not common. June- 

 Sept - /. viargiiiatus Rostk. 



11. Heads numerous (20-100), commonly 2- to 6-flowered, 



.stamens persistent, exserted; wet sandy soil, local 



/. bif^orus Ell. 



3. Leaves terete, hollow, more or less septate. 

 1 2. Stamens 6. 



13. Involucral leaf longer than the short-branched inflores- 

 cence; filaments longer than the anthers. 

 14. Heads 7-10 mm in diameter; flowers 3-4 mm long, 

 the petals ecjualling or exceeding the sepals; wet 

 ground, rare in n. 111. July-Aug /. uodosus L. 



14. Heads 1-1.5 cm in diameter; flowers 4-5 nun long, 



the petals much shorter than the sepals; ditches, 



common. July-Aug - /. torrcyi Coville 



1 3. In\olucral leaf much shorter than the long-branched 

 inflorescence; filaments about as long as the anthers. 



15. Branches ot the inflorescence widely divergent; 



sepals acuminate; sandy shores; Cook, Kane, 

 Lake, McHenry, and Menard counties. July-Aug. 



- /. articulatus L. 



15. Branches of the inflorescence erect or closely ascend- 

 ing; sepals obtuse or mucronate; wet soil; Cook, 

 Kane, Lake, and McHenry counties. July-Aug. 



/. richaidsojiianus Schult. 



12. Stamens usually 3. 

 16. Seeds caudate. 



