CLASSIFICATION. 91 



Genus 12. Polypogon. Inflorescence a spike-like 

 panicle ; spikelets single- flowered ; outer glumes nearly 

 equal, narrow, straight, concave, with cloven points, and 

 awns attached to the keels; flowering glume about half 

 the length of the outer ones, broadish, notched at the 

 summit, awned • palea also notched at the summit, thin, 

 transparent, narrow, and awnless ; scales oblong ; ovary 

 ovate ; filaments capillary, as long as the flowering 

 glume; anthers oblong ; styles two, far separated ; stig- 

 mas with long feathery hairs ; seed ovate, enveloped by 

 the flowering glume and palea, but not fastened to them. 

 Species 2 : — 1. Monspeliensis ; 2. littoralis. 



Genus 13. Agrostis. Inflorescence a more or less 

 spreading panicle ; spikelets one-flowered ; outer glumes 

 equal, narrow, pointed, awnless ; flowering glume smaller, 

 acuminate, generally awned ; palea smaller still, or ab- 

 sent. Species 4: — 1. alba ; 2. canina ; 3. setacea ; 4. 

 Spica-venti. 



Genus 14. Gastridtum. Outer glumes unequal, 

 acute, their base swollen, smooth, and shining. Species 

 1 : — lendigerum. 



Genus 15. Psamma. Panicle spike-like, cylindrical; 

 glumes stiff like chaff, flowering glumes awnless. Spe- 

 cies 1 : — arenaria. 



Genus 16. Calamagrostis. Inflorescence panicled; 

 spikelets one-flowered ; outer glumes nearly equal, 

 keeled; flowering glume thin, short, and narrow, awned, 

 a tuft of hairs at the base. Species 4: — 1. Epiyejos ; 

 2. lanceolata ; 3. strict a ; 4. Lapponica. 



Genus 17. Aira. Spikelets two-flowered ; outer 

 glumes two, equal, ovate-lanceolate, acute; flowering 

 glumes like the outer ones in form, but thinner ; palea 

 resembling the flowering glumes in height and texture ; 



