. Class-book of botany : being outlines of the structure, physiology and classification of plants : with a flora of the United States and Canada. Botany; Botany; Botany. PHYLLOTAXY, OR LEAF-ARRANGEMBNT. 47 221. Position upon the stem. Leaves are radical when they grow- out of the stem at or beneath the surface of the ground, so as to appear to grow froin the roots ; cauline when they grow from the stem, and ramial {ramus, a branch), when from the branches. 2:22. Insertion* upon the axis. The arrangement of the scales and young leaves in the bud appeals to be in close, contiguous circles. By th
. Class-book of botany : being outlines of the structure, physiology and classification of plants : with a flora of the United States and Canada. Botany; Botany; Botany. PHYLLOTAXY, OR LEAF-ARRANGEMBNT. 47 221. Position upon the stem. Leaves are radical when they grow- out of the stem at or beneath the surface of the ground, so as to appear to grow froin the roots ; cauline when they grow from the stem, and ramial {ramus, a branch), when from the branches. 2:22. Insertion* upon the axis. The arrangement of the scales and young leaves in the bud appeals to be in close, contiguous circles. By the development of the axis the leaves are separated, and their order variously modified, according to the following general modes:â Alternate, one above another on opposite sides, as in the elm. Scattered, irregularly spiral, as in the potato vine. Rosulate, clustered regularly, like the petals of a rose, as in the plantain and shephdhl's-purse. Fasciculate, tufted, clustered many together in the axil, as seen in the pine, larch, berberry. Opposite, two, against each other, at the same node. Ex. maple. Verticillate, or whorled, more than two in a circle at each node, as in the meadow-lily; trumpet-weed. We may reduce all these modes to 223. Two general types,âthe alternate, including all cases with one leaf at each node,âthe opposite, including cases with two or more leaves at each node. 224. The true character of the alternate type may be learned by an experiment. Take a straight leafy shoot or stem of the elm or rlax, or any other plant with seemingly scattered leaves, and beginning with the lowest leaf, pass a thread to the next above, thence to the next in the same direction, and so on by all the leaves to the top ; the thread will form a regular spiral. 225. Fasciculate leaves are the members of an undeveloped branch, and in. Phyllotaxy. 89, leafy branch of elm,âcycle }. 9'>. leafy branch of alder,â cycle $ ; 91, leafy branch of cherry,âcycle f â. Please note that
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