to be the function which stipules most frequently perform. See, for instance, Plates I., III., IV.

As a general rule such stipules fall with the leaf to

st

st

t

FIG. 126. YOUNG SHOOT OF VIRGINIAN CREEPER, × 2.
st, stipule; t, tendril.

which they belong.

ria (figs. 129, 130),

In some cases, however, as in Pette

they persist, and thus form a more

effective, or at least more permanent, protection to the

young bud.

There are, moreover, some cases in which stipules are developed so early that they serve not only to protect the younger leaves, but even the blade of the leaf to which they belong, as, for instance, in the Common Pea (fig. 26, p. 23), Lathyrus maritimus (fig. 296, p. 175), &c., Virginian Creeper (fig. 126), Vine (figs. 127, 128), Hop (fig. 48, p. 34). These will be alluded to in a subsequent chapter.

FIG. 127.-Tip of growing shoot, nat. size; l', 12, 13, three young leaves in order of succession; St, St2, St3, one of the pair of stipules belonging to each of the three leaves; t, tendril with its bract removed, showing the first fork.

FIG. 128.-Apical bud after removing the three leaves shown in fig.127, x 5; 7, the fourth leaf in succession; St, one of the stipules belonging to l; Sts, a stipule belonging to the fifth leaf; t, tendril almost enclosed in its bract; b, the bract, a modified leaf with three nerves in the sheathing base, which appears to consist of stipules adnate to the base of the petiole.

In Petteria ramentacea (figs. 129, 130) the stipules are at first small and obtuse. They have a covering of hair, and are axillary and slightly connate. The leaves are deciduous, but their stipules are persistent, and swell up or grow to considerable size, becoming thick and fleshy. Every lateral bud is, therefore, completely covered and effectually protected by the pair of stipules belonging to the leaf of the preceding year. These

stipules, as well as the persistent pedestal of the leaf to which they are attached, are densely lined on the inner face with pale brown hairs like a thick fur, while they are glabrous and dull olive-green externally.

In Guaiacum officinale (figs. 131, 132) the stipules are axillary and connate into

a rounded piece on each side of the stem on which they

connate, and form a sheath, which encloses the younger parts of the bud.

In Alstonia scholaris, belonging to the Apocynaceœ, the leaves (fig. 134) are whorled at the apex of each shoot in groups of six to nine, narrowly oblongelliptic, narrowed to both ends, but obtusely pointed.

The short petioles are semi-terete, flattened above, and furnished with a ligule or outgrowth from the base of the upper face, protecting the bud. This ligule is

triangular, obtuse, pale green, 1.5-2 mm. long; collectively they form a whorl, covering all but the extreme apex of the bud. (See also 14.)

In Spergularia rubra (fig. 135) the leaves are opposite, long, narrow, fleshy, and somewhat flattened above. The

FIG. 131.-Terminal shoot, nat. size; n, node; st', connate stipules; st", connate stipules covering the terminal bud.

FIG. 132.-Terminal shoot with lamina of leaves removed, x 2; st' st", stipules as in fig. 131; b, lateral bud.

stipules' are scarious, inserted at the node just beneath the leaves, so that they pass round the back of the latter, completely enclosing them in bud, and covering their bases even when fully developed. This is a most unusual arrangement. The stipules are also See Dickson, Journ. Bot. 1878, p. 316.

connate at the base, with an interpetiolar, free, ovate, acute piece, which is sometimes entire, sometimes divided at the apex into two or three setaceous teeth, as if these free portions consisted of one stipule from each

FIG. 133.-END OF SHOOT OF GARDENIA FLORIDA. Nat. size. L, L', a pair of leaves with their connate stipules, St', showing the fissured side only; L", L", the youngest unexpanded pair of leaves, with their stipules (St") completely investing the terminal bud.

leaf united. These stipules are very advanced in bud, and evidently attain full size long before the expansion of the leaves, many pairs of which they completely cover and protect. They are persistent, covering the bases of the leaves when full grown. They thus pro