Figure 1.

Some examples illustrating the variety of leaves. (a) The deciduous broad leaf of Liriodendron tulipifera (tulip tree) (leaf length typically about 12–15 cm). (b) The small evergreen leaves of Buxus sempervirens (boxwood). These leaves are much smaller, with lengths of 1.5–3 cm and are thicker and leathery, as is typical for leaves with a life span of 12 months and more. (c) Miconia astroplocama, as an example of a large tropical leaf. M. astroplocama also features a distinct venation system. (d) The large complex umbrella-like leaf system of Trevesia burckii, a plant living in rainforests of Southeast Asia. Leaflets are often deeply lobed, and toward the leaflet base, the lobation becomes so pronounced that the midrib appears to be a petiole. At the leaflet basis, however, the midribs of the leaflets are connected (“webbed”) by a sheet of leaf tissue. (e) The small fleshy (length about 1 cm) leaves of Haworthia cooperi, native to the Eastern Cape province in South Africa.