354 



POACE^, 



GRASS. 



A coarse perennial with creeping rootstocks, blades rigid, narrow 

 and involute. 



Very nearly related to Calamovilfa Hack. 



1. A. arenaria (L.) Link, Hort. Berol. 1:105 (1827). Beach- 

 Sand-geass. Arunclo arenaria L. Sp. PI. 82. (1753). 

 Psamma Uttoralis Beau v. Agrost. 176, t. 6,f. 

 1 (1812). Calamagrostis arenaria Eoth, Fl. 

 Germ. 1:34 (1788). 



Culms stout, GO-90 cm. high. Leaves 

 erect. Panicle dense, cylindrical, 12-25 cm. 

 long, 1-2 cm. broad. Si)ikelets compressed, 

 10-12 mm. long. Empty glumes com- 

 pressed, linear or lanceolate, scabrous on 

 the keel, first 1-nerved, second 3-nerved; 

 floral glume scabrous, compressed, lanceolate, 

 emarginate, often slightly mucronate; palea 

 4-nerved, hairs and rudiment less than half 

 as long as the spikelet. 



Atlantic coast and along the Great Lakes ; 

 seacoast of the British Isles. 



Owing to the abundaut hard rootstocks, sometimes 40 feet long, 

 it is excellent for preventing the drifting of sands along the shore. 

 70. (141a). Calamovilfa Hack. True Grasses, 113 (1890). 

 Spikelets 1-flowered, in panicles more or less diffuse, rachilla 

 articulate above the outer glumes, bearing a tuft of hairs around the 

 floral glume, not produced beyond it. The 2 empty glumes per- 

 sistent, unequal, chartaceous, thick, compressed-keeled ; floral glume 

 and palea of like texture, the former 1-nerved, awnless, the latter 

 2-keeled, 2- toothed. 



Very nearly allied to Ani'mophila and Calamagrostis. 

 There are three species, all North American. 



a. Spikelets 3.5-4.5 mm. long 1 



b. Spikelets 4-5 mm. long 2 



c. Spikelets 5-6 mm. long 3 



1. C. brevipilis (Torr.) Hack. 1. c. Arundo brevipilis Terr. 



Flor. U. S. 1: 95 (1824). Calamagrostis brevipilis A. Gray; Man. 



Fig. 5Q. — AmmophUa 

 arenaria. A, spike 

 let; a, lioret. (Scrib- 

 ner.) 



