38 GRAMINACEAE (GRASS FAMILY) 



PANICEAE (Millet Tribe). Spikelets in spikes or racemes or panicles, 

 falling off singly from the ultimate branches ; fertile spikelet with i terminal 

 pistillate flower, with or without a staminate one below it. Glumes rarely 

 awned, the awn straight. Lemma and palet firmer than the glumes, un- 

 awned in most. Stamens 3, rarely fewer. Grain inclosed, free, unfurrowed. 



A. Spikelets in i -sided spikes or spikelike racemes. 

 B. Lemmas not awned; glumes not spiny-hispid, hence spikes or spikelike racemes 



not bristly. 



C. Annual; lower glume very small; lemma with hyaline margin, not inrolled. 

 W. E. A bad weed in cultivated fields. (Gk. syn = with, therismos = crop; 

 hence crop-making.) Syntherisma sanguinale (CRAB GRASS) 



CC. Perennial; glumes equal or nearly so; lemmas without hyaline margin, in- 

 rolled. E. (Gk. paspalos = millet.) Paspalum distichum (JOINT GRASS) 

 BB. Sterile lemma awned; glumes spiny-hispid, making the spikelike racemes 

 somewhat bristly. W. E. (Gk. echinos = a hedgehog, chloa = grass; referring 

 to the bristling awns.) Echinochloa crusgalli (BARNYARD GRASS) 

 AA. Spikelets in open panicles, or if in a spikelike panicle this not i-sided. 

 D. Spikelets without an involucre of bristles, in an open panicle. (Latin name of 

 the Italian Millet.) Panicum (PANIC GRASS) 

 DD. Spikelets with an involucre of bristles, clustered in a single dense terminal 

 spikelike panicle. W. E. (Gk. chaeta = a bristle, chloa = grass; referring to 

 the bristly spikes.) Chaetochloa viridis (GREEN FOXTAIL) 



ORYZEAE (Rice Tribe). Perennial. Spikelets laterally flat, in a loose 

 panicle, with i terminal unisexual or perfect flower inclosed by a lemma and 

 a palet ; lemma boat-shaped, awnless, clasping the palet by a pair of strong 

 marginal veins, palet i-veined. Glumes none. Stamens 3. Grain fur- 

 rowed. Oryza saliva, cultivated rice, is in this tribe. Only the follow- 

 ing species. W. E. (Gk. omalos = resemblance, kenchros = millet ; hence 

 millet-like.) Homalocenchrus oryzoides (RICE CUT-GRASS) 



PHALAREAE (Canary-grass Tribe). Leaf blades flat. Spikelets of 

 i perfect flower with 2 sterile or staminate lemmas below it and falling 

 attached to it. Palet o-2-veined, inclosed in fertile lemma. Stamens 2-3. 

 Stigmas plumose. Grain unfurrowed, inclosed, free. 



A. Spikelets in spikelike or headlike clusters. 



B. Glumes equal; sterile lemmas awnless; stamens 3; plant not sweet-scented. 

 (Gk. phalaros = brilliant; referring to the shining seed.) 



Phalaris (CANARY GRASS) 



BB. Glumes unequal, lower about $ the upper; sterile lemmas awned; stamens 2; 

 plant markedly sweet-scented. W. (Gk. anthos = a flower, xanthos = yellow.) 

 Anthoxanthium odoratum (SWEET VERNAL GRASS) 

 AA. Spikelets in loose panicles. 



C. Plant not sweet-scented; spikelets i-flowered; sterile lemmas subulate. (See B.) 

 CC. Plants strongly sweet-scented; spiklets 3-flowered, the lower 2 flowers stami- 

 nate; staminate lemmas boat-shaped. (Gk. hieros = holy, chloe = grass; in 

 Europe strewn before church doors on saints' days.) Hierochloe (HOLY GRASS) 



AGROSTEAE (Timothy Tribe). Spikelets with i perfect flower. 

 Rachilla sometimes prolonged beyond the palets into a naked or plumose 



