128 BULLETIN 772, U. S. DEPARTMENT OF AGRICULTURE. 



the base (A. howellli Scribn.) or from about the middle (A. exarata 

 microphylla (Steud.) Hitchc.) or from just below the apex (A. spica- 



venti, A. ellio ttiana) . 

 The hairs on the callus 

 are usually minute, but 

 are half as long as the 

 lemma in A. hallii Vasey. 

 Three of our species are 

 annuals, A. spica-venti 

 L., introduced from 

 Europe; A. exigua 

 Thurb., of California; 

 and A. ellio ttiana Schult., 

 of the Southern States. 

 The genus furnishes 

 several species that are 

 important forage plants 

 either under cultivation 

 or in the mountain mead- 

 ows of the Western States. 

 The most important is 

 Agrostis palustris Huds. 

 (A. alba of authors 1 ) 

 (PI. XIII; fig. 67), 

 known usually as redtop 

 because of the reddish 



1 The name Agrostis alba L. 

 (Sp. PI. G3. 1753) is of doubtful 

 application. In the original 

 publication the name is founded 

 solely on the citation " Roy. 

 lugdb. 59 " (Royen, Flora Ley- 

 densis). Royen's citation of 

 synonym refers to Poa (appar- 

 ently P. nemoralis). There are 

 several sheets in Linnaeus's 

 herbarium, one of which bears 

 the name, Agrostis alba, in 

 Linnseus's script. These speci- 

 mens are the Agrostis alba as 

 generally understood, but, 



FIG- 07. Redtop, Agrostis falustris. Plant, X ; spikelet, open and closed, and floret, 



X 5. 



