Angiosp : i\ronocot : Gramineae. XVI. 



GRAMINEAE (314/4000), a great series of anemophilous Monocots. of 

 specialized habit, essentially rhizomatous, convergent with P.ilmsin arboreal examples 

 (Bambuseae), but more characterisiically reduced to herbaceous habit and prairie-land 

 formation. The essential departure of the grass-type centres in loss of the erect main 

 (primary) axis, and substitution of a perennial shoot-system at the ground-level, or 

 below, sending up erect slender shoots (culms) of seasonal habit, with greatly extended 

 internodes and distichous leaf-arrangement, with telescopic growth-eflfect. Rarely 

 monaxial (by culture) Zca, or annual (cull, cereals). The leaves are simple, with 

 sheathing base, ligular vestige of primary apex, and secondary linear lamina-extension 

 with parallel venation. The inflorescence is freely panicled, with many grades of 

 reduction-specialization ; the flowers on ultimate ramuli reduce their perianth- 

 segments in correlation with aggregation to special ' spikelet ' inflorescence-units, of 

 distichous construction, in which the subtending bract (lower pale) and 2-keeled 

 posterior prophyll (upper pale) acquire a special protective value, and the limiting 

 contact-cycle of 2 ' sterile glumes ' constitutes an additional involucre to the system. 

 In the limit the flowers of a spikelet may reduce to i only. The general scheme attained 

 is remarkably uniform ; herbaceous types of the N. Temp, express limiting cases of 

 reduction-specialization in connexion with xeiophytic prairie-conditions and adapta- 

 tion to a short season. 



As extreme examples of divergent lines in tropical regions, cf. : — 



I. Bambusa, Bamboo, 50, with associated genera (13) distinguished by special 

 details of flower and fruit. The t}pical primary giass of tropical forest-formation, 

 arboreal and gregarious, as nearer the prototype of the family. Woody culms 

 to 100 ft. are shot up in a month of the wet season, with branching heads of distichous 

 foliage and branching panicles of flowers ; the latter hermaphrodite, with full spikelets, 

 normal glumes and pales, vestigial perianth of 3 segments, 6 stamens (3 -)- 3), and 

 ovary with 3 free stigmatic plumes, unilocular with one anatropous ovule on the 

 posterior side (against rachis). The fruit is a dry caryopsis with endosperm storing 

 starch, and is shed as ' free ' grain. 



II. Zea Mais, expressing an advanced type of cereal, as a special limiting case 

 of tropical cultivation, is an artificial strain oi Euchlaena mexicana. Now monaxial, 

 nionocarpic, annual, diclinous; to 12-15 ft., the vegetative branching of .£'?^(-/i/<7(7;a 

 superseded : staminate flowers in a branched terminal di>tichous panicle, the spikelets 

 2-flowered and in pairs (T and T'), stamens 3, with normal glumes and pales. 

 Carpellary flowers in lateral systems, reduced to massive axis with high whorled 

 phyllotaxis (4-8), spikelets paired and 2-flowered, but one merely a rudiment ; ovary 

 with large ovule and single style-filament, to 6 in. long (collecting ' silks ' of young 

 'cob '). Fruit as naked grain, not detached, growth of pales and formerly protective 

 glume suppressed ; seed large, confluent with ovary-wall ; endosperm solid with packed 

 starch : cult, in many vars. 



III. Saccharum oflB.cinarum, Sugar-cane, cult, in Tropics to S. Europe ; 

 6-12 ft. high arjd 2 in. diam, ; herbaceous type of seasonal savannah. Stem annulate, 

 with short internodes (3-6 in.); panicle terminal, 1-2 ft., pyramidal, plumose, multi- 

 branched ; spikelets on end-ramuli paired (sessile and stalked, T and T'), i -flowered, 

 no awns but the glumes densely hairy ; stamens 3, stigmas 2, lodicules functional : 

 seed enclosed in pales, spikelet abstricted, and dispersal by aid of tufted glumes. A non- 

 flowering var. cult. 



IV. Oryza sativa, Rice, Swamp-type, of E. Asia, the oldest food-grain, cult, in 

 vars.: a much reduced form, 2-3 ft., with small panicle, 6 in., spikelets reduced to 

 I flower, glumes small, pale awned (or not), stamens 3-I-3, stigmas 2, lodicules 

 present. Spikelet detached in fruit, with seed enclosed in folded bristly pale (8 mm.) 

 with awn, 8 mm. Endosperm solid with packed starch. 



As Indian Bamboos, cf. : — 



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