(GRASS FAMILY.) 545 



(C. bullata, Ell.) Pine-barren swamps, Florida, and northward. Culms 

 l - 2 high. Leaves narrowly linear, keeled, rather rigid. Pcrigynia occa- 

 sionally nearly smooth. 



= = Periyyma smooth. 



73. C. riparia, Curtis. Sterile spikes 4-6, dark brown; fertile spikes 2- 

 3, oblong-cylindrical, sterile at the summit (1 '- 2' long), on erect peduncles ; 

 perigynia ovate-oblong, obscurely nerved, tapering -into a smooth 2-cleft beak, 

 longer than the oblong brown awned scale. Deep marshes, Florida to South 

 Carolina. Culms stout, 2 -3 high, rough above, shorter than the broad (') 

 smoothish and glaucous leaves and bracts. 



74. C. bullata, Schk. Sterile spikes 2-3, long-peduncled ; fertile spikes 

 1-2, oblong or oval (!' long), sessile, or on very short exserted peduncles ; peri- 

 gynia globose-ovate, much inflated, strongly nerved, smooth and shining, slender- 

 beaked, longer than the oblong acute scale. Swamps, South Carolina, and 

 northward. Culms 1 - 1 J high, shorter than the linear leaves and bracts. 



ORDER 160. GRAMINE^E. (GRASS FAMILY.) 



Chiefly herbs. Stem (culm) mostly hollow and with closed joints. 

 Leaves alternate, 2-ranked, narrow and entire. Sheaths open or split 

 on one side, and usually prolonged into a membranaceous or fringed 

 appendage (ligula) at the base of the blade. Flowers in spiked or 

 panicled spikelets, consisting of 2-ranked imbricated bracts or scales; 

 of which the exterior or lower ones, subtending one or more flowers, 

 are called glumes, and the two inner ones, enclosing the 1-celled 1-ovuled 

 ovary, and 1-11 (commonly 3) hypogynous stamens, are called palece. 

 Perianth none, or composed of 1 - 3 minute hypogynous scales (squamu- 

 Ice). Anthers versatile, 2-celled. Styles 2-3, with hairy or plumose 

 stigmas. Fruit a caryopsis (grain). Embryo placed on the outside and 

 near the base of mealy albumen. Koot fibrous. 



Synopsis. 



TKEBE I. OR YZE/E. Spikelets 1-flowered, mostly imperfect. Glumes none. Pale2. 

 Stamens 1-11. 



1. LEERSIA. Flowers perfect, compressed, panicled. Palese unequal, ciliate. 



2. ZIZANIA. Flowers monoecious ; the pistillate and staminate ones in the same panicle. 

 69. LUZIOLA. Flowers monoecious ; the pistillate and staminate ones in separate panicles. 



3. HYDROCHLOA. Flowers monoecious ; the pistillate and staminate ones in separate spikes. 

 60. MONANTHOCHLOE. Flowers dioecious, in terminal spikes. 



TRIBE II. A GROSTIDEJE. Spikelets 1-flowered, or with the pedicel of a second 

 flower above. Glumes 2. Paleae mostly 2, the lower one often awned. Stamens 1-3. 

 Spikelets in open or closely spiked panicles. 



* Glumes united at the base, strongly compressed-keeled. 



4. ALOPECURUS. Lower palea awned on the back, the upper wanting. Flowers spiked. 



46* 



