156 GRASSES OF IOWA. 



thin, containing the loose seed. Culms wiry or rigid. Leaves involute, 

 the throat usually bearded, and sheaths often enclosing the panicles. 

 (Name from the Greek word for seed, and to cast forth.) 



Bentham 5: .Hooker give the number of species as 80; the same 

 number is given by Hackel. The species are found chiefly in temperate 

 and tropical America; a few in tropical Africa and Asia. 



KEY TO THE SPECIES OP SPOROBOLUS. 



Panicle contracted, spike-like. 



Spikelets 3. 5 mm. long or over. 



Plant tall, panicle terminal, flowering glume exceeding the upper 



empty glume 5. longifolius. 1 



Plant smaller, panicles terminal and lateral, flowering glume equal- 

 ing the empty glumes 5. vaginae florus.* 



Spikelets 3 mm. long or less. 



Sheaths inflated, base of panicle usually included 5" neglectus. 3 



Sheaths not inflated, panicle exserted S. cuspidatus . 4 



Panicle open, pyramidal. 



Spikelets about 2 mm. long 5. cryptandrus . 6 



Spikelets 4 to 5 mm . long 6\ lielerolepisS 



1. SPOROBOLUS LONGIFOLIUS. 



Sporobolus longifolius Wood. Class-book. 775. 1861. 



Sporobolns longifolius (Torr.) Wood. Nash in Britton and Brown. III. 

 Fi. 1: 151. f.-342. 1896. Scribner. Am. Grasses. Bull. U. S. Dept. Agrl. 

 Div. Agros. 7: 126. f. 120. 1900. (3ded.) 



Sporobolus asper Vasey. Contr. U. S.Nat. Herb. 3: 59. 1892. (Not 

 Kunth. Enum. 1: 210. 1833.) 



Sporobolus asper Kunth in part. Watson and Coulter. Gray. Man. 

 Bot. 645. 1890. (6th ed.). Scribner. Grasses. Tenn. Bull. Univ. 

 Tenn. Agrl. Exp. Sta. 7: 72, 1890. 



