50 CONTKIBUTIONS FROM THE NATIONAL HERBARIUM. 



KEY TO THE SPECIES. 



Hairs of the pedicels very few and short or none 1. S. cirratum. 



Hairs Of the pedicels long and silky, abundant. 



Peduncles long and slender, much exserted 2. S. neomexicanum. 



Peduncles short, stout, little if at all exserted 3. S. scoparium. 



1. Schizachyrium cirratum (Hack.) Woot. & Standi. N. Mex. Agr. Exp. Sta. Bull. 



81: 30. 1912. 

 Andropogon cirratus Hack. Flora 1885: 119. 1885. 

 Type locality: Western Texas. 



Range: Mountains of southern New Mexico and Arizona and adjacent Mexico. 

 New Mexico: Star Peak; near Silver City; Mangas Springs; Dog Spring. Upper 

 Sonoran Zone. 



2. Schizachyrium neomexicanum Nash; Woot. & Standi. N. Mex. Agr. Exp. Sta. 



Bull. 81:29. 1912. 

 Andropogon neomexicanus Nash, Bull. Torrey Club 25: 83. 1898. 

 Type locality: ^Vhite Sands, New Mexico. Type collected by Wooton. 

 Range: New Mexico. 



New Mexico: Crawfords Ranch; Organ Mountains; mountains west of Grants 

 Station; Wliite Sands; Buchanan. Plains and low hills, in the Lower Sonoran Zone. 



3. Schizachyrium scoparium (Michx.) Nash in Small, Fl. Southeast. U. S. 59. 1903. 

 Andropogon scoparius Michx. Fl. Bor. Amer. 1: 57. 1803. 



Type locality: "Habitat in aridis sylvarum Carolinae." 



Range: British America to Texas, Florida, and Mexico. 



New Mexico: Coolidge; San Lorenzo; Pecos; Clayton; Trout Spring; Taos; 

 Raton Mountains; Sandia Mountains; Mogollon Mountains; White Mountains; Pecos 

 Valley. Plains and low hills, in the Upper Sonoran and Transition zones. 



5. AMPHILOPHIS Nash. 



Tufted perennials with mostly flat leaves and showy, often silvery, white panicles, 

 the axis short, making the panicle appear fanlike, or elongated; racemes usually 

 numerous, the internodes with thickened margins, the median portion thin and 

 translucent; pedicels ciliate with usually long hairs; first glume 2-keeled, the second 

 1-keeled; lemma hyaline, very narrow, stipelike, gradually merging into an awn; 

 stamens 3 ; styles distinct. 



KEY TO THE SPECIES. 



Hairs on the rachis and pedicels shorter than the spikelets 1. A. wrightii. 



Hairs on the rachis and pedicels longer than the spikelets. 



Awns 10 mm. long or less; panicles usually small 2. A. saccharoides. 



Awns more than 10 mm. long; panicles large 3. A. barbinodis. 



1. Amphilophis wrightii (Hack.) Nash in Britton, Man. 71. 1901. 

 Andropogon wrightii Hack. Flora 1885: 139. 1885. 



Type locality: "New Mexico." Type collected by Wright (no. 2104). 



Range: Southern New Mexico and Arizona and northern Mexico. 



New Mexico: Hillsboro {Metcalfe 1371). Dry hills, in the Upper Sonoran Zone. 



2. Amphilophis saccharoides (Swartz) Nash; Woot. & Standi. N. Mex. Agr. Exp. 



Sta. Bull. 81:30. 1912. 

 Andropogon saccharoides Swartz, Prodr. Veg. Ind. Occ. 26. 1788. 

 Type locality: Jamaica. 

 Range: Western Texas and southern Arizona to Mexico and the West Indies. 



