=Elliptic= differs from the oblong in having the sides gradually tapering to either end from the middle. The European beech (Fig. 104) has elliptic leaves. (This tree is often planted in this country.) [Illustration] =Lanceolate=, four to six times longer than broad, widest below the middle, and tapering to either end. Some of the narrow-leaved willows are examples. Most of the willows and the peach have oblong-lanceolate leaves. [Illustration] =Spatulate=, a narrow leaf that is broadest toward the apex. The top is usually rounded. [Illustration: FIG. 104.--ELLIPTIC LEAF OF PURPLE BEECH.] [Illustration: FIG. 105.--OVATE SERRATE LEAF OF HIBISCUS.] [Illustration: FIG. 106.--LEAF OF APPLE, showing blade, petiole, and small narrow stipules.] [Illustration] =Ovate=, shaped somewhat like the longitudinal section of an egg: about twice as long as broad, tapering from near the base to the apex. This is one of the commonest leaf forms (Figs. 105, 106). [Illustration] =Obovate=, ovate inverted,--the wide part towards the apex. Leaves of mullein and leaflets of horse-chestnut and false indigo are obovate. This form is commonest in leaflets of digitate leaves: why? [Illustration] =Reniform=, kidney-shaped. This form is sometimes seen in wild plants, particularly in root-leaves. Leaves of wild ginger are nearly reniform. [Illustration] =Orbicular=, circular in general outline. Very few leaves are perfectly circular, but there are many that are nearer circular than any other shape (Fig. 107). [Illustration: FIG. 107.--ORBICULAR LOBED LEAVES.] [Illustration: FIG. 108.--TRUNCATE LEAF OF TULIP TREE.] The shape of many leaves is described in combinations of these terms: as =ovate-lanceolate=, =lanceolate-oblong=. The shape of the base and apex of the leaf or leaflet is often characteristic. The base may be =rounded= (Fig. 104), =tapering= (Fig. 93), =cordate= or heart-shaped (Fig. 105), truncate or squared as if cut off. The apex may be blunt or =obtuse=, =acute= or sharp, =acuminate= or long-pointed, =truncate= (Fig. 108). Name examples. The shape of the margin is also characteristic of each kind of leaf. The margin is =entire= when it is not indented or cut in any way (Figs. 99, 103). When not entire, it may be =undulate= or wavy (Fig. 92), =serrate= or saw-toothed (Fig. 105), =dentate= or more coarsely notched (Fig. 95), =crenate= or round-toothed, =lobed=, and the like. Give examples.