HITCHCOCK — PLANTS OF AMES, IOWA. 523 



Zan'xicheli.ia palustris, L. Spec. 



Ponds and slow streams; not uncommon. 

 Naias FiiExiLis, Rostk. & Schum. Fl. Sedin. 1824. 



Ponds; becoming scarce. 



CTPERACE^E. 



Cyperus diandrus, Torr. Cat. PI. N. Y. 1819. 



Wet sandy places; scarce. 

 Var. CASTANEUS, (Pursh) Torr. I.e. — C. flavescens, \ax.casta- 



nens, Pursh, Fl. 

 Wet sands ; abundant. 

 C. aristatus, Rottb. Gram. 



Wet sand ; not uncommon. 

 C. SCHWEiNiTZii, Torr. Cyp. 



Sandy soil ; frequent. 

 C. FiLicuLMis, Valil, Euuni. il. 



Sandy hills ; frequent. 

 C. erythrorhizos, Muhl. Gram. 



River banks; abundant. 

 C. ESCULENTUS, L. Spec. 



Low ground ; abundant. 

 C. strigosus, L. Spec. 



Low or sandy ground; abundant. 

 Var. robustior, Kunth, Enum. ii. 



Low ground ; common. 

 Ej.eocharis palustris, (L.) R. Br. Prod. Fl. Nov. Hoi. 1810 (by 

 implication). — Scirpus palustris, L. Spec. 



Wet places ; common. 



E. ACicuLARis (L.) R. Br. 1. c. — Scirpus acicidaris, L. Spec. 



Muddy banks of ponds and streams; common. 

 Scirpus puxgens, Vahl, Enum. ii. 



N\'et clay ; scarce. 

 S. LACUSTRis, L. Spec. 



Sloughs, common. 

 S. FLUViATiLis, (Torr.) Gray, Man. 1st ed.— *S. maritimus, L., var. ? 



fluviatilis, Torr. Cyp. 

 Marshes ; infrequent. 



S. ATROViRENS, Muhl. Gram. 

 Sloughs ; common. 



Ertophorum lixeatum, (Michx.) Benth. & Hook, Gen. PI. iii. 2, 



1SS3. — Scirpus lineatum^ Michx. Fl. 

 Wet places; scarce. 



Bentham and Hooker by a slip say, "Hie includinuis . . . . E. liiieaUis, Mich." 

 Miciiaux is not reallv the author of this combination. 



