. Textbook of botany. Botany. eTB«¥- GP A PAM«.IAR PLANT upward. But it is not very strong, and when it is a few inches in length its weight and that of the leaves make it bend over; from this time on, unless care is taken to train it upward on a trellis or other support, the stem sprawls on the surface of the ground. 6. Leaves. — The secondary leaves (a name given to all the leaves that are formed after the two seed leaves) are pro- duced at intervals along the stem. They are alternately arranged — that is, at one point on the stem only one leaf arises, and the leaf next above will be not on
. Textbook of botany. Botany. eTB«¥- GP A PAM«.IAR PLANT upward. But it is not very strong, and when it is a few inches in length its weight and that of the leaves make it bend over; from this time on, unless care is taken to train it upward on a trellis or other support, the stem sprawls on the surface of the ground. 6. Leaves. — The secondary leaves (a name given to all the leaves that are formed after the two seed leaves) are pro- duced at intervals along the stem. They are alternately arranged — that is, at one point on the stem only one leaf arises, and the leaf next above will be not on the same side but on a different side of the stem. Each leaf has two parts, the leaf-stalk and the blade (Fig. 3). The blade is the large, flat portion of the leaf. It has a lobed outline, the three or five lobes being pointed, and the edge of each lobe irregularly toothed. There are many hairs growing on both the upper and lower surfaces of the leaf, as well as on the leaf-stalk and on the stem and branches of the plant. If the leaf be held up between the eye and a window, one can see in the blade many light green lines, the veins. Five large veins spread out from the point where the blade is attached to the leaf-stalk; as these main veins spread out in the blade they give off branches, the branches branch, and so on untU the whole system of veins looks like a network. It is in the leaf that much of the food is manufactured which is to be used in the growth of the plant, and the veins are useful in two ways:. Fig. 3- - Portion of a cucumber stem bearing a leaf and a 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 Allen, Charles E. (Charles Elmer), b. 1872; Gilbert, Edward Martinius, joint author. Boston, New York [etc. ] D. C. Heath & co
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectbotany, bookyear1917
