164 GRASSES OF IOWA. 



short-awned or mucronate on the back below the pointless apex. Stamen 

 one, opposite the i -nerved palet. Grain linear-oblong, free." A peren- 

 nial, rather sweet scented grass, with simple and uprighl 

 like culms 2 to 7 feet (5-20 dm.) high, bearing an ample, compound, 

 terminal panicle, its branches in fours and fives; the broadly linear-lan- 

 ceolate, flat leaves 4 to 6 lines (8-12 mm.) wide, with conspicuous li- 

 gules. Spikelets green, often purplish-tinted. (From a Greek word, 

 the name in Dioscorides for a kind of grass.) 



Bentham and Hooker and Hackel give the number of species as 2. 

 Both species occur in northern Europe and northern North America. 



KEY TO THE SPECIES OF CINNA. 



Spikelets 2 mm. long or over, empty glumes unequal C. arundinacea. 1 



Spikelets 11 mm. long, empty glumes nearly equal .... C. latifoliar 



1. CINNA ARUNDINACEA. 



Cin?ia arundinacea L,. Sp. PI. 5. 1753. Watson and Coulter. Gray. 

 Man. Bot. 649. pi. S. f. 1. 1890. (6th ed.) Scribner. Grasses of Tenn. 

 Bull. Univ. Tenn. Agrl. Exp. Sta. 7: 73. /. 94. 1894. Scribner. Bull. 

 U. S. Dept. Agrl. Div. Agros. 7: 140. /. 134. 1900. (3d ed.) Beal. Grasses of 

 N. A. 2: 319. 1896. Nash in Britton and Brown. 111. Fl. 1: 158. /. 360. 

 1896. Vasey. Contr. U. S. Nat. Herb. 3: 57. 



Agrostis Cinna Lamark. 111. 1: 162. 1791. 



Muhlenbergia Cinna. Trin. Dis. 1. 191. 1824. 



Blyttia suaveolens Fries. Mant. 2: 2. 



