. Plant life and plant uses; an elementary textbook, a foundation for the study of agriculture, domestic science or college botany. Botany. 2o6 LEAVES pinnate type. (The word means feather-like.) Most com- mon trees and shrubs have pinnately-veined leaves. In this type there is a central midrib from which branches are given off somewhat as harhs are given off from the shaft of a feather. (See Figure 6g.) Another common type of the net-veined leaf is the palmate type. (The word means palm- like.) Palmate leaves have a number of principal nerves or veins which arise from the base of the blade so
. Plant life and plant uses; an elementary textbook, a foundation for the study of agriculture, domestic science or college botany. Botany. 2o6 LEAVES pinnate type. (The word means feather-like.) Most com- mon trees and shrubs have pinnately-veined leaves. In this type there is a central midrib from which branches are given off somewhat as harhs are given off from the shaft of a feather. (See Figure 6g.) Another common type of the net-veined leaf is the palmate type. (The word means palm- like.) Palmate leaves have a number of principal nerves or veins which arise from the base of the blade somewhat as spread fingers arise from the palm of the hand. The common plan- tain has palmate leaves; so has the geranium. (See Figure yo) A palm-leaf fan is an example of a palmate leaf of a Fig. 6g.—Twig of elm showing pin- nate venation of the alternate leaves and their toothed margins. B. Shape. — The shape of a leaf is a characteristic which is not very constant. That is, the shapes of leaves vary more or less as their surroundings vary. Thus, for example, some plants which grow part in and part out of water, such as the water hemlock, have submerged leaves which are very different in shape and structure from those which develop in the air. This tendency to vary in shape is not a property equally possessed by all leaves. Leaves, like all other organs, vary in their power to vary. Many plants have leaves of distinct and characteristic shape which vary but little and furnish a sure means of identifying the plant. Many. 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 Coulter, John G. (John Gaylord), b. 1876. New York, American Book Co
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectbotany, bookyear1913
