. College botany; structure, physiology and economics of plants. Botany. 120 COLLEGE BOTANY and that most of the reserve food is stored around the embryo instead of in the cotyledons. The seeds of the beet, tomato> pepper, buckwheat and many of our common weeds belong to this type, but owing to their small size are not so satisfactorj' for study. Germination of the Castor-Oil Seed.—This process is very similar to that of the bean, but the cotyledons are covered for. Fig. 85.—Seed of castor-oil plant; (a) and {b) upper and lower surfaces: (c) after removal of the seed coat: (d, e) cotyledon
. College botany; structure, physiology and economics of plants. Botany. 120 COLLEGE BOTANY and that most of the reserve food is stored around the embryo instead of in the cotyledons. The seeds of the beet, tomato> pepper, buckwheat and many of our common weeds belong to this type, but owing to their small size are not so satisfactorj' for study. Germination of the Castor-Oil Seed.—This process is very similar to that of the bean, but the cotyledons are covered for. Fig. 85.—Seed of castor-oil plant; (a) and {b) upper and lower surfaces: (c) after removal of the seed coat: (d, e) cotyledon showing leaf characters. some time by the endosperm, which they gradually absorb. As the endosperm disappears, the cotyledons become green and more leaf-like and frequently persist for a long time. Therefore, the cotyledons sen^e first for the absorption of stored food and later as foliage. The Corn Type.—This is a monocotyledonousi type in which the food is stored in the endosperm. It is not a simple seed, but a true caryopsis fruit (page 112) in which the ovary coats have united with the seed coats. Therefore, it is not strictly com- parable to the seeds of the bean and castor-oil bean. It is flattened and somewhat wedge-shaped, the edges rounded and the large end smooth or indented. On one side is a groove within which the embryo is clearly visible. If we cut the grain longi- tudinally, we find the parts as follows: the radicle or primary. 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 Cook, Melville Thurston, 1869-1952. Philadelphia and London, J. B. Lippincott Company
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Keywords: ., bookcentury1900, bookdecade1920, booksubjectbotany, bookyear1920
