. Elementary botany . Botany. ROOT that is, as acropetal branches of another root — they are said to be adventitious. The difference between adventi- tious and normal lateral roots is well illustrated by considering the rOot-system of Dicotyledons and Monocotyledons. One of the general characteristics of a Dicotyledon is that its embryo in the seed has two cotyledons { Bean, Hazel, Oak). Frequently the root-system of Dicotyledons is formed after the manner described as occurring in the Bean, and well illustrated by fig. 4. The embryo of a Monocotyledon, on. Fig. 5.—Development of a typical
. Elementary botany . Botany. ROOT that is, as acropetal branches of another root — they are said to be adventitious. The difference between adventi- tious and normal lateral roots is well illustrated by considering the rOot-system of Dicotyledons and Monocotyledons. One of the general characteristics of a Dicotyledon is that its embryo in the seed has two cotyledons { Bean, Hazel, Oak). Frequently the root-system of Dicotyledons is formed after the manner described as occurring in the Bean, and well illustrated by fig. 4. The embryo of a Monocotyledon, on. Fig. 5.—Development of a typical Monocotyledon. the other hand, possesses only one cotyledon { Grasses, Lilies). Nearly always the root-system of a Monocoty- ledon develops in a manner entirely different from that pursued by the Bean. The young primary root (r) of the embryo grows for a short time only and produces at the most few lateral roots, eventually shrivelling up; but, sooner or later, lateral roots arise successively higher up the stem, first on the hypocotyl (a), then on the stem {a)—as is denoted in fig. 5. Consequently, in full-grown Monocotyledons practically the whole root-system is adventitious, and there is no main-root with branches. [In fig. 5 the roots have pulled the base of the shoot down into the soil.]. 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 Groom, Percy, 1865-1931. London : G. Bell
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectbotany, bookyear1898
