Arundinaria.] LXXVIII. GRAMINEiE. 561 



ally in Bamboos). Leaves alternate, consisting of a tubular sheath, split 

 to the base, and a narrow, linear or lanceolate blade (in Bamboos joined 

 to the sheath by a petiole) ; inner face of sheath often prolonged into a 

 membranous or coriaceous ligule. Flowers mostly bisexual, arranged in 

 distichous 1- or many-flowered spikelets. Spikelets supported at the base 

 and often enclosed by two or more bracts (empty glumes), the axis or 

 rachis bearing one or numerous distichous bracts (flowering glumes). 

 Each flowering glume bears in its axil, on the short axis of the flower, the 

 palea, a membranous, generally transparent bract, mostly 2-keeled. Be- 

 tween palea and the flowering glume are a 1 -celled ovary, with 2 distinct, 

 often lateral, styles, or 1 terminal style, generally 2- or 3-fid, surrounded 

 by 3, 6, rarely more or fewer stamens, and 2 or 3 membranous, often cili- 

 ate scales (lodicules). Anthers 2-celled, cells contiguous, opening longi- 

 tudinally. Fruit a 1 -seeded caryopsis, pericarp generally closely adhering 

 to the testa, and sometimes (Oats, Barley) adhering to the palea and flower- 

 ing glume. Embryo at the base of the albumen on the outside, small, 

 its position conspicuous on the surface when the pericarp is thin and closely 

 adhering to the testa ; not conspicuous when the pericarp is thick, coriaceous, 

 woody or fleshy. Albumen farinaceous, composed of thin-walled cells, filled 

 those near the outside with albuminous (nitrogenous) substances, the mass of 

 the cells chiefly with grains of starch. Embryo consisting of a broad cotyle- 

 donary body (scutellum) contiguous to the albumen, a basal radicle and the 

 plumule. When germinating, the scutellum remains enclosed in the seed, 

 the radicle protrudes and lateral root-fibres emerge from it, while the plu- 

 mule, in the opposite direction, unfolds its leaves. During the process of ger- 

 mination the starch of the albumen is gradually converted into sugar and 

 other soluble substances, which pass into the embryo through the scutel- 

 lum, and serve as the food of the plant in the first stage of its growth. 



Grasses comprise upwards of 4500 species, grouped under numerous tribes. 

 Those here described all belong to the tribe Bambuseos, which are charac- 

 terised by woody, mostly perennial stems (culms) with numerous branches 

 at the nodes, leaves petiolate, articulate at the base of the petiole, decid- 

 uous, leaving the branchlets surrounded by persistent, generally coriaceous 

 sheaths, stamens 3 or 6, rarely more, style 1, 2-3-fid, rarely undivided. 

 As in Palms, the vascular bundles in the inner part of the Bamboo stem 

 are composed of vessels, cells, and fibres, while those near the surface 

 consist of fibres only. These are close together, almost confluent, forming 

 the hard outer rind of the Bamboo. At the nodes the vascular bundles 

 cross from one side of the stem to the other, forming the principal mass of 

 the hard horizontal partition walls which separate the joints. The stem 

 of Bamboos with hollow joints has much less cellular tissue than the stem 

 of Palms, and the vascular bundles differ in shape also. Morphologi- 

 cally and with regard to its anatomical structure, the underground stem 

 (rhizome) of Bamboos has more analogy with the perennial stem of Palms 

 like Phoenix, Borassus, Cocos ; but these points demand farther study. 

 An excellent monograph of Bamboos by General Munro is published in 

 the 26th volume of the Transactions of the Linnean Society, where the 

 number of species described is 170. 



2n 



