GRAMINEAE 21 



flattened, usually ciliate ou the keels, awnless, about equal in length, 

 the second much narrower than the first. Leaves clothed with minute 

 hooked prickles. 



Spikelets partly curved, Ij^' long. 1. //. Virginicus. 



Spikelets fiat, 2"-2'' long. 2. H. oryzoides. 



1. H. Virginicus ( Willd.) Britton. Culms l°-3° high with a finally 

 long exserted panicle : spikelets crowded at the ends of the branches, 

 closely appressed and somewhat curved around the branches : stamens one 

 or two. — Rather common in low wet woods. August-October. 



2. H. oryzoides ( L. ) Poll. Larger than the last with a larger diffusely 

 branched panicle : stamens three. — Growing in dense masses around 

 swamps and less luxuriantly along streams. Well distributed through- 

 out. August-October. 



13. PHALARIS L. 



Flowers in panicles which are often very spike-like. Spikelets one- 

 flowered with five glumes, the first and second large, keeled and thick, 

 the third and fourth rudimentary (reduced to scales or bristles), the fifth 

 subtending a similar palet and the flower. 



Panicle not spike-like ; grass of wet grounds. 1. P. arundinacea. 

 Panicle spike-like; grasses of waste places. 



Spikelets green, narrowly keeled. 2. P. CaroUniana. 



Spikelets white with green lines, broadly keeled. 3. P. Canariensis. 



1. P. arundinacea L. Reed Canary Grass. Perennial, 2°-5° 

 high, with long flat leaves ; first and second glumes not winged. — Well 

 distributed in wet grounds in the northeastern part. May-June. 



2. P. CaroUniana Walt. Southern Canary Grass. Smooth annual 

 about 2° high, with spike-like panicle 1^-3' long and about 6'^ wide, 

 oblong in outline. — Rarely adventized along railroads from Sheffield to 

 Courtney. May-June. . 



3. P. Canariensis L. Canary Grass. Annual 2°-3° high, with 

 long-peduncled spike-like panicles f^-U^ long, 5'^-7'' wide at base and 

 tapering to the summit. — Rarely occurs in waste places and along rail- 

 roads. May-June. 



14. ANTHOXANTHUM L. 



Glumes five, the first shorter than the second, the third and fourth 

 empty, two-lobed and awued, the fifth shorter, about the length of the 

 palet. 



1. A. odoratum L. Vernal Grass. Annual about 2° high, with 

 numerous slightly hairy, flat leaves : spikes long-exserted, 2^-3^ long : 

 third glume bearing an awn inserted on the back about the middle, and 

 the fourth an awn inserted near the base. — Rarely adventized along the 

 railroads at Courtney. May-June. 



