15 



In the Texas Exhibit there are specimens 6 feet three inches high. 



47. P. Urvilleanum, Kth. Southern California. 



48. P. velutinosufn, Wees. Arizona. 



49. P. verrucosum, Muh.l. New England to Texas. 



50. P. virgatum, Linn. New England to Florida, and West to 



Rocky Mountains. Tall Panic, grass. Switch grass. 

 A tall perennial grass, 3 to 5 feet high, growing mostly in clumps 

 in moist or even in dry sandy soil, very common on the sea-coast, 

 and also in the interior to the base of the Rocky Mountains. This 

 is a good and prolific grass if cut when .young ; when ripe it be- 

 comes harsh and unpalatable. It forms a large constituent of the 

 native grasses of the prairies, particularly in moist localities. 



51. P. viscidum, Ell. New England to Texas. Moist meadows. 



52. P. Xanthophysum, Gray. Massachusetts and New York to 



Minnesota. 



53. P. unisetum, Trin. (Setaria uniseta, Four.) Texas. 



Oplismbnus, Beauv. 



Spikelets with one terminal perfect flower and a rudimentary one, 

 awned, clustered along the distant sessile branches of the simple 

 panicle, with three empty glumes; the lowest glume nearly as long 

 as the others and longer awned ; the flowering glume awnless and 

 hardened with the palet as in Panicum. 

 1. O. setarius, R. ds S. (Panicum hirtellum, Lam.) Florida to Texas. 



Sbtaeia, JBcanv. 



Spikelets in a cylindrical spike like, or sometimes interrupted 

 panicle. Below the articulation of the spikelets are several, usually 

 many, bristles, which are supposed to be abortive branchlets and 

 persistent after the fall of the spikelets. The spikelets contain one 

 terminal fertile flower, (its glume and palet indurated and striate,) 

 and usually a lower male or sterile one. Empty glumes 3, the 

 lower one small, the second usually shorter than the third, the flow- 

 ering glume indurated ; the second flower when present consisting 

 of a thin palet and sometimes three stamens. 

 1. S. composita, Kth. Florida to Texas. 



A tall, coarse, broad-leaved grass resembling Hungarian grass. 

 It frequently grows 5 to 6 feet high. 



