PLANT ORGANS AND ORGANISMS 
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Gleditschia; if these become again divided, as in many Acacia 
species, the leaf is termed tripinnate. Examples of decompound 
leaves seen in Cimicifuga and Parsley. 
Leaf Texture. — Leaves are described as: 
Membranous, when thin and pliable, as Coca. 
Succulent, when thick and fleshy, as Aloes, and Live Forever. 
Coriaceous, when thick and leathery, as Eucalyptus, Uva Ursi and 
Magnolia. 
Leaf Color. — Petaloid, when of some brilliant color different from 
the usual green, as the Coleus and Begonia, and other plants which 
are prized for the beauty of their foliage rather than their blossoms. 
Leaf Surface.— Any plant surface is: 
Glabrous, when perfectly smooth and free from hairs or protuber- 
ances. Example: Tulip. 
Glaucous, when covered with bloom, as the Cabbage leaf. 
Pellucid- punctate, when dotted with oil glands, as the leaves of 
the Orange family. 
Scabrous leaves have a rough surface with minute, hard points. 
Pubescent, covered with short, soft hairs. Example: Strawberry. 
Villose, covered with long and shaggy hairs. Example: Forget- 
me-not. 
Sericious, silky. Example: Silverleaf. 
Hispid, when covered with short, stiff hairs. Example: Borage. 
Tomentose, densely pubescent and felt-like, as the Mullein leaf. 
Spinose, beset with spines, as in the Thistle. 
Rugose, when wrinkled. Example: Sage. 
Verrucose, covered with protuberances or warts. 
Duration of Leaves. — Leaves vary as to their period of duration. 
They are: Persistent, or evergreen, if they remain green on the tree 
for a year or more. 
Deciduous, if unfolding in spring and falling in autumn. 
Caducous, or fugacious, if falling early in the season. 
Parts of Typical Leaf.- — The parts of a typical leaf are petiole or 
leaf stalk, lamina or blade, and stipules. 
Gross Structure and Histology of the Petiole.— The petiole in 
Monocotyledons is usually a broadened, sheathing basal structure 
which connects the lamina to the stem. Into this a set of closed 
