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CHAPTER XI

LEAVES—FORM AND POSITION


Leaves may be studied from four points of view,—with reference (1) to their kinds and shapes; (2) their position, or arrangement on the plant; (3) their anatomy, or structure; (4) their function, or the work they perform. This chapter is concerned with the first two categories.

Fig. 88.—A Simple Netted-veined Leaf.

Fig. 89.—A Simple Parallel-veined Leaf.

Fig. 90.—Compound or Branched Leaf of Brake (a common fern).

Kinds.—Leaves are simple or unbranched (Figs. 88, 89), and compound or branched (Fig. 90).