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pairs of stipules without any leaves at all. The rings thus become separated in Magnolia, while in the Beech the first internodes are not developed, leaving a distinct band of rings, to mark the season's growth. The Magnolia is therefore less desirable to begin upon. The branches are swollen at the beginning of a new growth, and have a number of leaf-scars crowded closely together. The leaf-scars are roundish, the lower line more curved. They have many dots on them. From each leaf-scar runs an irregular line around the stem. This has been left by the stipules. The flower-scar is on the summit of the axis, and often apparently in the axil of a branch, as in Horsechestnut. Sometimes the nearest axillary bud is developed; sometimes there are two, when the branch forks. The axillary buds seldom grow unless the terminal bud is interrupted. The tree therefore has no fine spray. LILAC _(Syringa vulgaris_). Ask the scholars to write a description of their branches and to compare them with Horsechestnut. These papers should be prepared before coming into the class, as before. The buds are four-sided. The scales and leaves are opposite, as in Horsechestnut. The outer pair sometimes have buds in their axils. Remove the scales one by one with a knife, or better, with a stout needle. The scales gradually become thinner as we proceed, and pass into leaves, so that we cannot tell where the scales end and leaves begin. After about six pairs are removed, we come, in the larger buds, to leaves with axillary flower-clusters. The leaves grow smaller and the flower-clusters larger till we come to the centre, where the axis is terminated by a flower-cluster. There is a great difference in the buds on different bushes and on shoots of the same bush, some being large, green, and easy to examine, others small, hard, and dark-colored. It is better, of course, to select as soft and large buds as possible for examination. [Illustration: FIG. 14.--Lilac. I. Branch in winter state: _a_, leaf-scar; _b_, bud-scar (reduced). 2. Same, less reduced. 3. Branch, with leaf-buds expanded. 4. Series in a single bud, showing the gradual transition from scales to leaves.] That the scales are modified leaves is plainly shown by the gradual transition they undergo, and also by the fact that buds are developed in their axils. If any of these can be shown to the pupils, remind them of the experiment where the top of a seedling Pea was cut off and buds
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