128 BULLETIN 772, U. S. DEPARTMENT OF AGRICULTURE. 
the base (J., howellii Scribn.) 
microphylla (Steud.) Hitchc.) 
or from about the middle (A. exarata 
or from just below the apex (A. spica- 
v en ti , A. elliottiana) . 
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 J., elliottiana 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 Hucls. 
(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. 63. 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. nemoraUs). There are 
several sheets in Linnseus's 
herbarium, one of which bears 
the name. Agrostis alba, in 
Linnsus's script. These speci- 
mens are the Agrostis alba as 
generally understood, hut. 
Fig. 67. — Redtop, Agrostis palustrii 
Plant, X 
X 5. 
•pikelet, open and closed, and floret. 
