33 TRIANDRIA.— MONOGYNIA, 



HAB. In salt marshes. July — Aug. If. An inch high, 

 growing in patches, like moss. 



7. S. intermedins: culms cespitose, quadrangular, sul- 



cate ; spike ovate-oblong, acute ; glumes rather 

 acute ; stamens 3 ; style 2-cleft ; seed broad-obo- 

 vate, compressed ; tubercle distinct. 

 HAB. Muddy banks of rivers. Sept. If . Ascending, 

 3 — 4 i n , high ; bristles 6 ; tubercle very minute. 



8. £. planifolius : culm triquetrous ; radical leaves flat; 



nearly equalling the culm ; spike terminal, oblong, 

 compressed, shorter than the cuspidate bracts at the 

 base. 

 HAB. Begs and wet woods. May — June. If. Cespi- 

 tose ; leaves carinate ; spike 6-Jl. yellowish ; inf. 

 glumes very large, hracte.iform. 



9. S. subterminalis : culm floating, sulcate, inflated, leafy 



below ; spike solitary, somewhat terminal, lanceo- 

 late ; style 2-cleft ; seed triquetrous. 

 HAB. Ponds and rivulets. Aug. If. Whole plant, 

 except the spike, under water ; culm, when dry, much 

 roughened by the contracting medulla ; leaves chan- 

 nelled. 



10. S. cespitosus, /3. callosus : culm cespitose, terete ; 



spike ovate, few-flowered ; glumes thickened and 

 cartilaginous at the tips ; the inferior ones bractei- 

 form, as long as the spike ; sheaths with rudiments 

 of leaves. 

 HAB. On high mountains. July. If . A span high ; 

 culm with imbricated sheaths at the base ; spikes yel- 

 lowish ; bristles 6. 



t t Style filiform , not bearded, deciduous. 



11. S. americanus: culm nearly naked, triquetrous; 

 sides concave ; spikes lateral, (1 — 5,) ovate, con- 

 glomerate, sessile ; glumes round-ovate, mucro- 

 nate ; seed triquetrous, acuminate. 

 HAB. In salt marshes, and on the banks of rivers, 

 July— Aug. U . Culm 3-5 feet high, sometimes leafy 

 at base. 

 12. S. debilis: culms cespitose, deeply striate ; spikes 

 about 3, lateral, ovate, sessile ; glumes ovate, 

 obtuse, mucronate. 



