. Botany for secondary schools; a guide to the knowledge of the vegetation of the neighborhood. Plants. FERTILIZATION AND POLLINATION 135. 224. Flower of larkspur. 225. Envelopes of a larkspur. There are five wide sepals, the upper one being spurred. There are four small petals. ent plants. Fertilization resulting from self- or close-pollina- tion is close-fertilization. Fertilization resulting from cross- pollination is cross-fertilization. In many cases cross-pollination is essential for good seed or fruit development. Corn, if close-pol- linated, pro- duces imperfect W M ears. Culti- vated
. Botany for secondary schools; a guide to the knowledge of the vegetation of the neighborhood. Plants. FERTILIZATION AND POLLINATION 135. 224. Flower of larkspur. 225. Envelopes of a larkspur. There are five wide sepals, the upper one being spurred. There are four small petals. ent plants. Fertilization resulting from self- or close-pollina- tion is close-fertilization. Fertilization resulting from cross- pollination is cross-fertilization. In many cases cross-pollination is essential for good seed or fruit development. Corn, if close-pol- linated, pro- duces imperfect W M ears. Culti- vated plants frequently ex- hibit decreased vigor by close- pollination. 279. Usually the pollen is dis- charged by the bursting of the anthers. The commonest method of discharge is through a slit on either side of the anther. (Fig. 218.) Some- times it discharges through a pore at the apex, as in azalea (Fig. 220), rhododendron, huckleberry, wintergreen. In some plants a part of the anther wall ...Mjf/% . raises or falls as a lid, as in barberry (Fig. 'viffe^ 221)> Dmc cohosh, May apple. The open- i) ing of an anther (as also of a seed-pod) is known as dehiscence. When an anther or seed-pod opens it is said to dehisce. 280. Most flowers are so constructed as to increase the chances of cross-pollination. The commonest means of insuring cross- pollination is the different times of matur- ing of stamens and pistils in the same Mower. In most cases the stamens mature 826. Stamens of lark- first: the flower is then /irotrnuitlrous. spur, surrounding Ttri , . ... _ . _ the pistils, When the instils mature firsl the flower is. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Bailey, L. H. (Liberty Hyde), 1858-1954. New York, Macmillan
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectplants, bookyear1913
