140 GRAMINEAE 



especially at the nodes ; sheaths finely papillose, shorter than the internodes, 

 the ligule very short; blades about an inch long, pilose on the upper surface, 

 inrolled; spike 1 to 3 inches long, pale; glumes and lemmas sparsely long- 

 pilose and more or less papillose, the glumes 2 lines, the lemmas 3 lines long. 



Only known from the type collection. "Moist plains of the upper Sacramento, 

 near (hico, California, June, 1890, by Prof. E. L. Greene." 



Bef. — ORCCTTi.i GREENEI Vasev, Bot. Gaz. 10: 146. 1891. 



4C. ARUNDO L. 



Spikelets 3 or i-tlowered in large terminal panicles. Glumes narrow, sub- 

 equal, 3-nerved, smooth, acute or acuminate, about as long as the spikelet, 

 Rachilla smooth. Lemma thin, membranaceous, 3-nerved, 2-toothed at apex, 

 mucronate between the teeth, long-pilose on the back. Tall reed-like grasses, 

 with hollow culms, and broad flat blades. — Species about 6, in the warmer 

 regions of the Old AYorld, 1 introduced in America. (An ancient Latin name.) 



]. A. donax L. Giant-reed. Culms stout, as much as 20 feet high, and an 

 inch in diameter at base, from rough knotty branching rhizomes; blades 

 numerous, broad, Hat, 2 to 3 inches wide on the main stem, smaller on the 

 branches, the base cordate and more or less liairy-tufted : panicle large, 1 to 

 2 feet long ; spikelets about 6 lines long. 



A native of the Old World, freriuently cultivated for ornament in tropical 

 America. Rather common in gardens in the southern U. S. and escaped along 

 irrigating ditches from Texas to central and southern California. The only Cali- 

 fornia specimen in tlie National Herbarium is from the Alameda marshes, Davy 

 in 1808. 



Kefs. — Aeundo donax L. Sp. PI. SI. 1753; Davy in .Jepson, Fl. W. Mid. Cal. .59. 1901; 

 Abrams, Fl. Los Aug. 44. 1904. 



17. PHRAGMITES Trin. 



Spikelets loosely 3 to 7-Howered, in large terminal panicles. Glumes unequal, 

 lanceolate, acute, shorter than the spikelet. Rachilla clothed with long silky 

 hairs. Lemmas narrow, long"'-acuminate, glabrous, the lowest longer, equaling 

 the uppermost florets, empty or subtending a staminate flower. Tall reed-like 

 perennials. — Species 3, 1 cosmopolitan, 1 in Asia, and 1 in South America. 

 (Greek phragmites, growing in hedges.) 



1. P. communis Trin. Common Reed. Culms as much as 12 feet high, from 

 long creeping rhizomes, these sometimes appearing on the surface of the ground 

 as long leafy stolons as much as 30 feet long; blades as much as 2 inches wide, 

 flat, the base somewhat narrowed, not hairy; panicle 6 to 1.5 inches long; 

 spikelets 6 to 7 lines long. 



Fresh-water swamps, marshes and around springs, through the temperate 

 regions of the world. 



Locs. — Mendocino, Brottm 943 ; Suisun marshes, Davii 4095 ; Concord, Elmer 4541 ; San Ber- 

 nardino, Parish 5111; Newberry, Chase 5779. 



Refs. — Phraomites communis Trin. Fiind. Agrost. 134. 1820; Thurb. in Wats. Bot. Cal. 

 2 : 300. ISSO. P. vulgaris B. S. P. Prel. Cat. N. Y. 69. 188S ; Davy in Jepson, Fl. W. Mid. 

 Cal. 59. 1901. Arundo ■vulgaris Lam. Fl. Fran^. 3: 615. 1778. Phragmites phragmites Karst. 

 Deutsche Fl. 379. 1880. Arundo phragmites L. Sp. PI. 81. 1753. 



48. TRIDENS Roem. & Schult. 



Spikelets 3 to many-flowered, the uppermost staminate or reduced, in open 



or contracted panicles. Glumes glabrous. Lemmas 3-nerved, more or less 



bidentate, the middle nerve often produced between the teeth into an awn, the 



nerves and callus densely villous. Palea shorter than the lemma, long-ciliate 



