11 



This is, next to the Festucece, the largest tribe in the 

 order, numbering seven hundred species arranged in 

 forty- six genera. The species are distributed through- 

 out all the temperate and colder regions of the world 

 and many occur within the Tropics. The genus Ac/rostiSj 

 from which the tribe derives its name and from which 

 comes the word "agrostologist,"has about one hundred 

 species, found in all parts of the world, especially in 

 the north temperate zone. Some of our most important 

 meadow grasses — notably Herd's-grass and timothy — 

 belong to this tribe. 



Aristida Linn.* Epicampes Presl.* 



Stipa Linn. * Polypogon Desf. 



Oryzopsis Michx.* Limnodia L. H. Dewey.* 



Milium Linn.* (Thurberia Benth.) 



Muhlenbergia Schreb.* Arctagrostis Griseb. 



Bracliyely train Beauv.* Cinna Linn." 



Lycurus Kunth. Agrostis Linn.* 



Pereilema Presl. Gastridium Beauv. 



Heleocbloa Host.* Calamagrostis Roth.* 



Phleum Linn.* Aminopbila Host.* 



Alopecurus Linn.* Calamovilfa Scribn.* 



Coleanthus Seid. Apera Adans. 



Phippsia R. Br.* Lagurus Linn. 

 Sporobolus R. Br.* 



Tribk IX. — Avenea'. 



Spikelets two- to several-flowered; outer empty glumes usually 

 longer tban tbe first floral glume; one or more of the floral 

 glumes awned on tbe back or from between tbe teetb of tbe bifid 

 apex ; awn usually twisted or geniculate ; tbe callus, and usually 

 tbe joints of tbe rachilla, hairy. 



A tribe comprising twenty-three genera and over 

 three hundred species widely distributed in the tem- 

 perate regions of both the Old and the New World, 

 particularly abundant in South Africa and Australia, 

 a few extending beyond the arctic circle. 



