PEAIEIB GRASSES. 607 



dasystachyum Vasey, A. tencrmii. Vasey, Elymus sibiricus L., var. americanus 

 Watson, aud E. mollis Trin. 



Another list of one Inindred and two species comprises plants which 

 are known to attain their eastern limits within the Red River basin, being- 

 common thence westward on the plains and often in the Rocky Moinitains 

 and to the Pacific. In this list are twenty Compositse, most of them 

 abundant and showy; four species of Cai'ex; and twelve grasses, namely, 

 Bechnannia cnicceformis Host, var. imiflora Scribner, Stipa spartea Trin., S. 

 viridula Trin., Sporoholus cuspidatus Torr., Avena pratensis L., var. aiiiericana 

 Scribner, Schedonnardus texatms Steud., Boutelomi oligostacliya Torr., Distich- 

 lis maritima Raf., var. stricta Thurber, Poa tenuifolia Nutt., Festuca scahrella 

 Torr., Agropyrmn ylaucum R. & S., var. occidentale, V. & S., aud Elymus 

 sitanion Schultes. 



The most plentiful and valiuxble grasses in this nt)rtheastern part of 

 the great prairie region of the continent are as follows, with notes of their 

 habit of growth and comparative importance: 



Spartina cynosuroides Willd., the prevailiug and ofteu the only grass of sloughs 

 (which is the term commonly applied to unry depressions of the xjrairie), making good 

 hay; also largely used as fuel by immigrants in many districts remote from timber 

 and railways, and as thatch by Mennonite colonists in Manitoba. 



Beckmannia eruccefonnis Host, var. uniflora Scribner, frequeut or common on wet 

 ground, where water stands a part of the year, from Port Arthur, Lake Superior, to 

 the Rocky Mountains, extending northeast to Hudson Bay aud Lake Mistassini. 



Panicum capillare L., common along streams, and in sandy cultivated fields. 



Panicum virgatum L., fi'equent, often abundant, on somewhat moist portions of 

 the iirairie, especially in southwestern Minnesota aud South Dakota. 



Andropogon furcatus Mnlil., abundant on rather dry tracts in South and North 

 Dakota, where it is usually called ''blue joint," and is highly esteemed for hay; less 

 common in Manitoba; whitish and glaucous, not abundant, among the sand dimes of 

 the Sheyeune delta of Lake Agassiz. 



Andropogon scoparius Michx., abundant, occupying drier laud than the last. 



Chrysopugon nutans Jienth., covatnon or fveqiient in the Dakotas; less so farther 

 north; much cut for hay, with Andropogon furvatus and Panicum virgatum. 



Phalaris arundinacea L., abundant in marshes. 



Hierochloe borealis R. & S., very common on moist ground and along rivers and 

 lakes throughout this northern prairie region. 



