400 



MAIZE 



MAIZE 



consists of cells capable of rapid growth. Hence 

 the base of the sheath is ready at any time to 

 grow, and if the plant is blown over by the wind, 

 growth takes place, and the plant is thus assisted 

 into an upright position. Another point of interest 

 is that a number of the internodes are alternately 

 grooved or flattened. Those persons who have 

 made a "corn-stalk fiddle" will remember that it 

 was this peculiar flattening, which accommodates 

 the ears, that rendered possible the manufacture 

 of the crude musical instrument. The sap bundles 

 of the corn stem are isolated and of the closed 

 collateral type. 



Leaves. — The leaves of corn are two-ranked ; that 

 is, they alternate on opposite sides of the stems. 

 Each leaf may be divided into three parts, — a 

 sheath, which is open along one side, a ligule, or 



keep the leaf -blade perfectly flat. In hot, dry 

 weather, water is lost from these cells and the 

 leaf-blade rolls up and thus protects itself against 



Fig. 600. High northern com. Cross between large yellow 

 flint and Improved Learning corn ; fonr years crossing. 

 Wakefield, twenty miles north of Ottawa, Canada. 



membranous outgrowth at the top of the sheath, and 

 the blade. The ligule has been appropriately called 

 the rainguard, as it acts in such a way that rain- 

 water with dust particles held in solution, which 

 runs down the grooved surface of the 

 leaf, runs off on either side on reach- 

 ing the ligule and does not run into 

 the space between the stem and 

 sheathing base, where dirt might other- 

 wise easily accumulate. The folds in 

 the margin and base of the leaf, which 

 are formed because the edge grows 

 more rapidly than the middle, are in- 

 genious natural or mechanical contri- 

 vances to ease the strain on the leaf- 

 blade when the wind blows. If a 

 microscopic section is made of the 

 leaf-blade, peculiar fan-shaped cells are 

 found distributed in the upper epider- 

 mis between the prominent parallel 

 veins. These are bulliform cells and in 

 ordinary weather absorb water and 



Fig. 601. Ears from the stalks shown in Fig. 600. 



desiccation and controls the normally high rate of 

 transpiration, or water loss. 



Flowers. — The flowers of maize are arranged in 

 clusters in two difi'erent parts of the plant. The 

 male (staminate) flowers together form the termi- 

 nal tassel of the plant, while the female (pistillate) 

 flowers (Fig. 515) are placed on the cob, sur- 

 rounded by the husks in the axils of the lower, or 

 usually the middle leaves of the stem. The stami- 

 nate flower cluster is known as a panicle of spike- 

 lets. Each ultimate division of the tassel (pani- 

 cle) is a spikelet. Each spikelet consists of two 

 dry scales (lower glumes) subtending two flowers 

 of three stamens each. Each staminate flower is 

 surrounded by a flowering glume (lemma) and a 

 palea on the inside. When the anthers are mature, 

 they dangle at the ends of long filaments, and thus 

 the dry, smooth pollen-grains are consigned to the 

 wind. The pistillate flowers are placed in even- 

 numbered rows on the fleshy axis known as the 

 cob. Each spikelet on this axis consists of two 

 flowers, subtended by two glumes more or less 

 horny or leathery. One pistillate flower is abortive 

 and is represented solely by a flowering glume and 

 a palea, while the other pistillate flower, with sub- 

 tending, flowering glume and palea, has an ovary 

 surmounted by a long, hairy style, showing, under 

 the microscope, two longitudinally directed vascu- 

 lar bundles. Each style, or thread of silk, is hairy, 

 to entrap the round, smooth pollen-grains, which 



Fig. 602. Early- maturing low-growing com adapted to North Dakota and 

 the northern states. It may yield forty or more bushels per acre. (Hartley.) 



