. The cereals in America. Grain. STRUCTURE OF WHEAT 31. the slits which are formed in the upper end of the two com- partments. This process takes place apparently in a very short space of time. (49) The ovulary is one-seeded and is sur- mounted by two feathery stigmas which prior to the opening of the flower are erect and adjacent. As the flower opens the" stigmas fall apart to receive the pollen. Pollination being eflfected, the stigmas soon wither and the ovulaiy rapidly enlarges. The development of the ovule (seed) from the period of flowering to maturity is very rapid and emphasizes t
. The cereals in America. Grain. STRUCTURE OF WHEAT 31. the slits which are formed in the upper end of the two com- partments. This process takes place apparently in a very short space of time. (49) The ovulary is one-seeded and is sur- mounted by two feathery stigmas which prior to the opening of the flower are erect and adjacent. As the flower opens the" stigmas fall apart to receive the pollen. Pollination being eflfected, the stigmas soon wither and the ovulaiy rapidly enlarges. The development of the ovule (seed) from the period of flowering to maturity is very rapid and emphasizes the importance of proper soil and climatic conditions at that time. (49) 57. The True Flower. — The ovulary, stigma and stamens are enclosed within two chaffy parts, the inner of which is called a palea and the outer and lower the flowering glume. These parts collectively constitute the flower of the wheat. The awn or beard is borne on the flowering glume and varies greatly in length in differ- ent varieties or even in the same spike, or may be entirely wanting. In some varieties the awns are deciduous or partly so upon ripening. They vary in color from very light yellow to black. Organs of reproduction in wheat : a, ovulary ; i, styles and stigmas ; c, anthers ; li, filaments of stamens. Upper left illustration shows flower before opening ; upper right illustration shows flower about to open and protrude an- thers. (After Hays.) 58. The Spikelet.—Two to five flowers are enclosed within two chaffy and still harder parts called empty or outer glumes. This is called collectively a spikelet. There is considerable variation in the number of flowers maturing seed, due to variety and environment. In the varieties of common wheat there are generally three or more flowers in each spikelet, which usually matures two or three grains,—more commonly two. The outer glumes differ from those in rye by being oval rather than awl-. Please note that these images are extracted from scanned p
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Keywords: ., bookauthorhuntthom, bookcentury1900, bookdecade1900, bookyear1904
