SEDGE FAMILY. 465 



III. Glumaceous Division. 



Flowers inclosed or subtended by glumes or husk-like 

 bracts ; no proper calyx or corolla, except sometimes mi- 

 nute bristles or scales which represent the perianth. Stems 

 of the straw-like sort, called culms. 



CXXXIII. CYPERACE^, SEDGE FAMILY. 



Some rush-like, others grass-like plants, with flowers in 

 spikes or heads, one in the axil of each glume, the glume 

 being a scale-like or husk-like bract. No calyx nor corolla, 

 except some vestiges in the form of bristles or occasionally 

 scales, or a sac which imitates a perianth; the 1-celled 1- 

 ovuled ovary in fruit an akene. Divisions of the style 2 when 

 tlie akene is flattish or lenticular, or 3, when it is usually tri- 

 angular. Leaves, when present, very commonly 3-ranked, and 

 their sheath a closed tube; the stem not hollow. A large 

 family, to be studied in tlie Manual, and too difficult for the 

 beginner. The most prominent genera are the following: 



* Flowers commonly all perfect. 



•»- Spikelets usually many-flotoered luith only one or two of the loioer 



scales without flowers. 



** Scales 2-ranked, the spikelet therefore flat. 



= No bristles about the akene, and no beak at its top. 



1. CYPERUS. Spikelets few-many-flowered, mostly flat and slender, 

 in simple or compound terminal umbels or heads. Culms mostly tri- 

 angular and simple, most of the leaves at the base. Many species in 

 low grounds ; three should be mentioned here : 



C. rotiindus, Linn. Nut Grass, Coco Grass. A bad weed in sandy 

 lands from L. I., S. ; early leaves grass-like and tufted, 3'-6' high, followed 

 later in the season by a single, leafless, triangular culm, 6'-20' high ; 

 umbel simple or slightly compound, about equaling its involucral leaves, 

 its rays few, and each one bearing 4-9 dark-chestnut, 12-40-flowered, 

 acute spikelets ; scales nerveless. The plant is introduced in the N. 

 It persists in the soil by means of little, nut-like tubers which are borne 

 from several inches to 4° away from the base of plant, on stolons. 



C. escul^ntua, Linn. Chufa. Cultivated, especially at the S., for 

 its edible tubers, which are clustered about the base of the plant, and 

 also wild ; early leaves 15'-30' high, slightly rough, about as long as the 

 stem ; umbel 4-7 -rayed, sometimes compound, much shorter than the 

 involucral leaves ; spikelets numerous and light colored, 12-30-flowered, 

 the scales nerved. The cultivated form rarely flowers in the N. 



flRVy's ^. F. & G. BOT. 30 



