immediately beneath it being strongest on the leading branches; they are also the first to resume growth in spring. All are covered with numerous scales, which consist of modified leaves. The actual number of scales varies greatly, according to the size of the bud. The accompanying figures would represent buds and scales about the middle of April, after growth has recommenced. The outer scales are the most coriaceous, and elongate slightly or not at all; the inner ones are transparent and membranous, elongating considerably in spring.

The true leaf (fig. 277) consists of a lamina, which becomes disarticulated (when about to fall) from a short persistent portion or pedestal, surmounting a basal portion which is decurrent upon the axis. Fig. 278 shows a small, slightly modified leaf-a form which occurs but sparingly.

The basal portion of the bud is covered with broad, triangular, acuminate scales (figs. 279, 280), with a more or less evident midrib, which seem to consist of the whole leaf modified. These are followed by a few oblong, obtuse, or subacute scales (figs. 281, 282) that are still coriaceous, but elongate slightly in spring in the case of the inner ones.

The innermost scales (figs. 283, 284, 285) are as long as the bud, or nearly so; but after the resumption of growth they soon extend beyond the coriaceous ones, keeping pace for a time with the elongating axis, and completely enclosing the young true leaves. These

inner scales elongate chiefly in the lower portion, which seems to correspond to the pedestal. They are, on the whole, more or less spathulate, but vary in form, and the apical portion seems to correspond to the lamina, because there is generally a trace of a joint or articulation. This apical portion is slightly more coriaceous and browner than the long and very membranous lower portion.

Some of the inner scales are more or less evidently trifid (fig. 284) or tridentate, the lateral lobes appearing to correspond to the shoulders seen below the pedestal of the normal and perfect leaf. The innermost scales (fig. 285) are suddenly widened at the apex, forming a hood or cap rolled round the apex of the bud and completely covering and protecting the young leaves.

CYCADACEÆ

In Cycas (Cycas revoluta) one tier of leaves is produced every year, all developing simultaneously. The bud is covered with a mass of imbricate scales. The latter are subulate, elongate, ending in a spine, dilated and triangular at the base, densely covered with a pale brown, woolly felt, erect or incurved in bud, ultimately spreading with age, but persisting for many years. Thus two sets of leaves are developed every year, each tier duly alternating.

In Zamia also (Zamia Fischeri) the buds are protected by numerous scales.

CHAPTER VI

ON THE FORMS OF STIPULES

THOUGH stipules do not show such endless differences in form as is the case with leaves, nevertheless they present an immense variety.

They may be orbicular, as in Tropaeolum ciliatum (fig. 312); semi-orbicular, as in Guaiacum officinale (fig. 30); ovate, as in Passiflora racemosa, Hop (fig. 47), and Abutilon megapotamicum; obovate, as in Bucklandia (fig. 190); oblong, as in Leea (fig. 188) and Alder (fig. 145); elliptic, as in Hazel Nut (fig. 212); spathulate; lanceolate, as in Paronychia serpyllifolia and Pyrus japonica; linear, as in Disanthus (Hamamelideae) and Ficus infectoria; filiform, as in Turkey Oak (Quercus Cerris); subulate, as in Mahonia and several species of Helianthemum; sagittate, as in Lathyrus pratensis (fig. 299) and L. maritimus; semi-sagittate, as in Lathyrus latifolius (fig. 300) and L. grandiflorus; reniform, as in Vallea (Sterculiacea); triangular, as in Ceanothus rigidus ; boat-shaped, as in Populus nigra (fig. 192); palmately lobed, as in Croton; laciniate, as in Trigonella laciniata ; pinnatifid, as in several species of Croton, Medicago and

Melilotus; pinnatipartite, as in Viola tricolor (fig. 27), Passiflora pinnatistipula, and Pomaria glandulosa; or palmatipartite, as in Althea rosea, A. ficifolia, Pterospermum acerifolium, &c.

In texture they may be foliaceous, as in the Heartsease; membranous, when thin, flexible, and almost transparent; scarious, when dry and coriaceous, as generally in the Beech and Hornbeam; spinous, as in Robinia (fig. 34); cirrhose, when produced into tendrils, as in Smilax.

In many cases the stipules are very small, sometimes quite minute, as in Hymenanthera (fig. 28), a plant belonging to the Violet family. The Holly is described in Bentham and Hooker's' Genera Plantarum' as exstipulate, but (fig. 29) there are minute black points at the base of the leaves, which appear to represent stipules. In others they are very large, as in the common Pea (Pisum sativum) (fig. 26), Lathyrus maritimus (fig. 296), and Bucklandia (fig. 190).

Many plants have stipules of different forms.

The stipules covering winter-buds are often different in form from those of the subsequent leaves (see, for instance, figs. 215–235).

Where stipules serve as bud-scales there is generally a series of different forms, from those of the outer scale to those of the ordinary leaf.

In the Thorn (Crataegus Oxyacantha) (fig. 286) the stipules on the leaves of the short lateral spurs and those

M

at the very base of the elongating shoots are minute and toothlike, or subulate, soon becoming brown and falling early. Those on the upper part of the elongating shoots

vary from unilateral, falcate, serrated, small but foliaceous organs, to large, half-cordate, simply or doubly serrate, shortly stalked, foliaceous, much-reticulated