. Practical botany. Botany. Pig. 87. Leaf scar of horse- chestnut /«, scars marking position of fibro- vascular bundles; len, lenticels. Twice natural size flowers may be destroyed by frost as the bud opens, and in that case no fruit scar will be left at the end of the season, the bud developing much like an ordinary leaf bud. The only way in which one can become thoroughly familiar with the course of development of shoots, flowers, and fruits from buds is to mark some buds like that shown at A in Fig. 76. This may be done by tying a bit of twine loosely above each bud; its history is then to
. Practical botany. Botany. Pig. 87. Leaf scar of horse- chestnut /«, scars marking position of fibro- vascular bundles; len, lenticels. Twice natural size flowers may be destroyed by frost as the bud opens, and in that case no fruit scar will be left at the end of the season, the bud developing much like an ordinary leaf bud. The only way in which one can become thoroughly familiar with the course of development of shoots, flowers, and fruits from buds is to mark some buds like that shown at A in Fig. 76. This may be done by tying a bit of twine loosely above each bud; its history is then to be fol- lowed for at least a year and recorded by means of frequent drawings. 92. The record; leaf scars. Kleaf scar is the place which was occupied by the base of the leafstalk while it remained attached to the shoot. Some of the things which can be learned from the study of leaf scars are the number, position, and arrangement of leaves on the shoot for several years back, the relative sizes of the leaves, and the mode of bud-bearing of the spe- cies studied, — whether there were accessory buds, or the buds were all axillary (Figs. 75 and 85). On careful examination of any large leaf scar, as that of ailanthus, horse- chestnut (Fig. 87), coffee bean, it is seen to be dotted with a considerable number of minute projections, fv. These mark the course of the fibro- vascular bundles from the leaf into the stem. In leaves of dicotyledons there are usually about as many such dots on the scar as there were principal veins in the leaf. "Why ?. Fig. 88. Lenticels, wild black cherry A, soon after the destruction of the stomata, to Avliich the len- ticels succeed; B, at end of first season's growth. One and one-half times natural size. 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 Bergen, Joseph Y. (Jos
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