30 Class III. Order III. 



species of Arundo, and differing from most othef grasses in 

 having a solitary stamen in each flower. Wet shady grounds. 

 August. Perennial. 



31. LEERSIA. 

 LEERSIA ORYZOIDES Swartz. Cut grass. 



Panicle loose ; spikelets triandrous ; keel of the 

 glumes ciliate. Sw. 

 Syn. PHALARIS ORTZOIDES. L. 



Stem about two feet in height. Leaves exceedingly rough 

 backward, so as to cut the hands if drawn across them; narrow, 

 on long rough sheaths. Panicle erect, spreading, with slender, 

 rough branches. Flowers very distinguishable by their oval 

 figure and white colour. Glumes of the corolla compressed, the 

 two valves shut together, so as to assume an elliptical form, with 

 the curvature on one side greatest. Keel of the valves ciliated, 

 giving the circumference of the flower a fringed appearance. 

 Wet places. \ugust. Perennial. 



LEERSIA VIRGINICA. fVilld. Virginian Cut grass. 



Panicle simple ; flowers monandrous, sparingly cili- 

 ate on the keel. 



Smoother than the preceding species, the flowers considerably 

 smaller and less ciliate, white. Damp woods, Oak island. 



August. 



32. PHALARIS. 



PHALARIS AMERICANA. Ell. American Canary grass. 



Panicle oblong, spiked ; glumes of the calyx boat- 

 shaped, serrulate ; corolla unequal ; rudiments hairy, 



Syn PHALARIS ARUKDINACEA. MX. 



CALAMAGROSTIS COLOR AT A. Nutt. 



A large, rank, aquatic grass, three or four feet high with a 

 panicle of pubescent flowers. In Muddy brook, near Jamaica 

 plain road. July. 



