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INTRODUCTION. 



Ill 



consists of three or more cbaff like scales, called glumes, of which the two 

 outer, or lowest, are usually empty, and are differ- 

 ently shaped from the others. The third and suc- 

 ceeding glumes, if there be more than three, are 

 the flowering glumes, each of which normally con- 

 tains a small scale, usually transparent and with two 

 lateral nerves; this is called the pale. "Within the 

 pale is the real flower consisting of minute scales, 

 usually only two, called lodicules, and three sta- 

 mens, rarely more or less, with long filaments, 

 supporting anthers which are attached by their 

 middle (versatile). In the centre, surrounded by 

 the stamens and lodicules, is the ovary, 1-celled, 

 and containing a single ovule. At the top of the 

 ovary are the two feathery styles. The grain, i.e., 

 the matured ovary, contains a single seed consolidated with the pericarp, 

 or outer skin of the grain. The embryo lies at one side at the base of 

 the seed, and is surrounded by a thick farinaceous substance known as 

 albumen or perisperm. 



The above are some of the prevailing characters of the family, but there 

 are many exceptions ; for instance, the stems of some of the perennial 

 kinds become woody, as in bamboos, many of which attain to the size of 

 trees, and their stems are frequently solid throughout. The greatest 

 variation occurs in the structure of the spikelets. They are sometimes 

 monoecious, as in Indian corn, which bears male and female clusters of 

 spikelets on different portions of the plant. The spikelets may be 1-flow- 

 ered {Plate E., Fig. 27), or 2-or more-flowered {Plate E., Fig. 26a, and 

 Plate E., Fig. 29a). The florets of each spikelet may be perfect {Plate 

 A., Fig. 1c), i.e., with both stamens and pistil, or with only one set of or- 

 gans (unisexual) {Plate A., Fig. 6a), or without either stamens or pistil 

 (neuter) ; and sometimes without even the pale, in which case the floret 

 is represented by a single scale or glume. In the same spikelet there may 

 be both perfect and imperfect florets {Plate A., Fig. 5, b). In rice the 

 lower empty glumes are minute, or reduced to bristles. In Panicum the 

 outer empty glume is usually very much smaller than the other {Plate A., 

 Fig. 4), whilst in Paspalum it is wanting altogether. The midrib of some 

 of the glumes, usually the flowering one, is often furnished with a bristle, 

 extending either from the tip or from its back ; this when of a certain 

 length is called an awn {Plate E., Figs. 25 and 26). These awns must be 

 carefully distinguished from other bristles which often occur at the base 

 of the spikelets in the form of an involucre. The true awn is represented 



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