Page:First course in biology (IA firstcourseinbio00bailrich).pdf/145

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walnut, butternut, red maple, honey locust, and sometimes in the apricot and peach.

If the bud is at the end of a shoot, however short the shoot, it is called a terminal bud. It continues the growth of the axis in a direct line. Very often three or more buds are clustered at the tip (Fig. 140); and in this case there may be more buds than leaf scars. Only one of them, however, is strictly terminal.

Fig. 140.—Terminal Bud between two other Buds.—Currant.

A bud in the axil of a leaf is an axillary or lateral bud. Note that there is normally at least one bud in the axil of every leaf on a tree or shrub in late summer and fall. The axillary buds, if they grow, are the starting points of new shoots the following season. If a leaf is pulled off early in summer, what will become of the young bud in its axil? Try this.

Fig. 141.—A Gigantic Bud.—Cabbage.

Bulbs and cabbage heads may be likened to buds; that is, they are condensed stems, with scales or modified leaves densely overlapping and forming a rounded body (Fig. 141). They differ from true buds, however, in the fact that they are condensations of whole main stems rather than embryo stems borne in the axils of leaves. But bulblets (as of tiger lily) may be scarcely distinguishable from buds on the one hand and from bulbs