222 GRASSES OF IOWA. 



lines (5-8 mm.) long, with smooth, empty glumes and hairy, two-lobed 

 and short-awned, flowering glumes. July-October. 



Triodia purpurea occurs only in sandy soil in southeastern Iowa. 



DISTRIBUTION. 



Ioiua. Moscow (Hitchcock) ; Iowa City (Hitchcock). 



North America. In sandy soil Maine to Ohio (Painsville, Beards- 

 lee), North Carolina (McCarthy), Florida (Duval County, Curtiss), 

 and along the Great Lakes; west to Nebraska (Hall and Harbour; 

 Rock County, Clements, 2883), Texas and New Mexico. 



5. KCELERIA. 



Koeleria Pers. Syn. PI. 1: 97. 1805. Scribner Bull. U. S. 

 Dept. Agr. Div. Agros. 20: 136. f. 105. [Rev. Ed.] 

 Airochloa Link. Hort. Berol. 1: 126. 1827. 

 Collinaria Ehrh. Beitr. 4: 147. 1789. 

 Lophocloa Reich. Fl. Germ. Exc. 42. 1830. 

 Aegialitis Trin. Fund. Agrost. 127. 1820. 

 Aegialina Schultes. Syst. Mant. II. 13: 222. 1824. 



Spikelets 3 to 7-flowered, crowded in a dense and narrow, spike- 

 like panicle. Glumes membranaceous, compressed-keeled, obscurely 3- 

 nerved, barely acute, or the flowering glume often mucronate or bristle- 

 pointed ; the empty ones moderately unequal, nearly as long as the spike- 

 ler. Stamens 3. Grain free. Tufted, with simple, upright culms, the 

 sheaths often downy; allied to Dactylis and Poa. (Named for Prof. 

 G. L. Koeler, an early writer on grasses.) 



Bentham & Hooker give the number of species as 12; Hackel rec- 

 ognizes 15, the same number being given by Scribner, one only occurs 

 in America. The genus is represented in Asia, northern Africa, North 

 America and South America, but chiefly in Europe, Ritcher giving 16 

 species. These no doubt are in part mere forms of some of the polymor- 

 phic species. 



1. KOELERIA CRISTATA. 



Koeleria cristata Pers. Syn. 1: 97. 1805. Watson and Coulter. 

 Gray Man. Bot. 659. pi. 10. [6th. Ed.] 



Koeleria cristata (L.) Pers. Beal. Grasses of N. A. 2: 445. /. 99. 

 1894. Nash in Britton and Brown. 111. Fl. 1: 194. /. 444. 1896. 

 Scribner. Bull. U. S. Dept. Agr. Div. Agros. 20: 136. /. 105. 1900. 

 (Rev. ed.) 



Koeleria nitida Nutt. Gen. 1: 74. 1818. 



Aira cristata L. Sp. PI. 63. 1753. 



