Elementary principles of agriculture Elementary principles of agriculture : a text book for the common schools . elementaryprinci02ferg Year: 1913 114 Elementary Principles of Agriculture drop of food at the base of the ovary. When the bee enters the flower to gather bee-bread (pollen) and the honey, or nectar, at base of pistil, some of the pollen is lodged on its head and legs and body. When it enters the next flower, some of this pollen is caught by the stigma. (Fig. 55.) Many kinds of flowers are solely dependent on the going and coming of insects to bring about pollination and, there- f
Elementary principles of agriculture Elementary principles of agriculture : a text book for the common schools . elementaryprinci02ferg Year: 1913 114 Elementary Principles of Agriculture drop of food at the base of the ovary. When the bee enters the flower to gather bee-bread (pollen) and the honey, or nectar, at base of pistil, some of the pollen is lodged on its head and legs and body. When it enters the next flower, some of this pollen is caught by the stigma. (Fig. 55.) Many kinds of flowers are solely dependent on the going and coming of insects to bring about pollination and, there- fore, the formation of fruit and seed. We used to think that flowers had their gor- geous colors to please man's fancy. We now know that it is to attract the lowly in- sects. Usually, night-bloom- ing flowers are white and give off their odors more strongly at night (study the tuberoses, rain lilies, night- blooming cereus, moon-flow- ers, etc.), in order to attract the night-flying moths. Blue and red flowers are day bloomers. 168. Growth of the Pollen Grains. The pollen grain is a very small body, consisting of one or two cells. When it is deposited on the moist stigma, it begins to grow a slender tube (pollen-tube) down into the ovary. 169. Fertilization. The pollen-tube produces a small cell that contains a nucleus that passes into and unites Fig. 56. Diagrammatic section of ovary and ovule at time of fertili- zation, m, micropyle; k, egg cell; The pollen tube has grown down through the style, between the walls of the ovary and ovule, to the egg cell, k, of the embryo sac.
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