LAMSON-SCRIBNER AND MERKTLL GRASSES OF ALASKA. G5 



3. Trisetum alaskanum Nash, Hull. N. V. Hot. (Sard. 2: 155. 1901. 



A tufted perennial 20 to 50 cm. high, with villous culms, pubescent blades and 



sheaths, and densely flowered, spike-like, contracted panicles 4 to 10 cm. long; spike- 

 lets 6 to 7 mm. long, 2 or 3-flowered; lemmas not exserted, hispidulous, the lower one 

 5 to 6 mm. long; awn about as long as the lemma. 



On open hillsides, Aleutian Islands, Alaska Peninsula, and southeastern Alaska. 



A doubtful species closely related to Trisetum spicaturn molle, from which it is 

 distinguished only by its larger spikelets and included lemmas. 



Trisetum flavescens (L.) Beau v. is reported from Port Clarence a but evidently 

 on an erroneous determination, the plant so named doubtless being Trisetum cernuum, 

 Avena subspicata of Griseb. in Ledeb. Fl. Ross, is Trisetum spicaturn molle, while 

 Avena sesquifiora of the same work is true Trisetum spicaturn. The range of Trisetum 

 canescens Buckl. is extended to Alaska by Beal b sub T. cernuum canescens, but he cites 

 no Alaskan material . 



13. AVENA L. 



Avena L. Sp. PI. 79. 1753. 



Spikelets 2 to 4-flowered, callus of the lemmas bearded; glumes membranaceous, 

 exceeding the lemmas in length; lemmas rounded on the back, 5 to 9-nerved with a 

 dorsal twisted awn. Native species, perennials with paniculate inflorescence and 

 usually large spikelets. 



1. Avena striata Michx. Fl. Bor. Amer. 1: 73. 1803. 



A slender, erect, glabrous perennial 30 to GO cm. high, with narrow, flat leaves, short 

 ligules, and simple, racemose, open panicles; spikelets about 12 mm. long, 3 to 0-flow- 

 ered, on slender pedicels; glumes acute, the first 1-nerved, the second 3-nerved; 

 lemmas 7-nerved, about 8 mm. long, much exceeding the palea, bearing a twisted 

 geniculate awn just below the acutely 2-cleft apex. 



Collected at Cook Inlet and extending eastward to New England and New York. 



Specimen examined: Kenai, Piper 4715. 



14. BECKMANNIA Host. 



Beckmannia Host, Icon. Gram. Austr. 3: 5. pi. 6. 1805. 



Spikelets 1 or 2-flowered, rather broad, compressed, closely imbricated in two rows 

 along one side of the rachis of the short spikes; rachilla articulated below the glumes; 

 glumes 2, inflated, boat-shaped. A rather tall, erect grass with flat leaves and a ter- 

 minal, narrow, elongated inflorescence. 



1. Beckmannia erucaeformis (L.) Host, Icon. Gram. Austr. 3: 5. pi. 6. 1805. 



Slough-grass. 

 Phalaris erucaeformis L. Sp. PI. 55. 1753. 



In sloughs and along the banks of streams, Porcupine River and the upper Yukon, 

 southward to Ontario, Iowa, and California; also in Europe and Asia. 



Specimens examined: Fort Yukon, Bates in 1889; Porcupine River, Turner in 

 1891. 



15. CATABROSA Beauv. 



Catabrosa Beauv. Ess. Agrost. 97. 1812. 



Spikelets small, usually 2-flowered, the rachilla articulated between the florets; 

 glumes 2, much shorter than the lemmas, unequal, scarious, very obtuse, or the upper 

 one crenulate at the apex; lemmas subcoriaceous, prominently 3-nerved, awnless. 

 A creeping aquatic grass with thin flat leaves and open, pyramidal panicles. 



"Kjellman in Nordenskiold, Vega-Exped. 2: 55. 1883. 

 b Grasses N. Amer. 2: 380. 1890. 



