Leaf of Virginia Creeper.
Here, side by side, the forms of the two leaves can be compared. On the right is the digitate leaf of the beautiful Virginia creeper, entirely harmless; on the left is the pinnate leaf of the poison-vine. The innocent plant is five-leaved; the noxious plant is three-leaved. But we should also notice particularly that the arrangement of the leaflets is quite different in the two plants. In the poison-vine, we see a pair of leaflets and a terminal odd one; whereas in the Virginia creeper, there is no pairing of leaflets whatever, but the five parts radiate from a centre. All the leaflets come out together from one point at the tip of the leaf-stalk.
Plants there are with digitate leaves, having three, five, seven, nine, or more leaflets. Clover has digitate leaves of three leaflets, while the leaves of the buck-eye and horse-chestnut have five, seven, and nine leaflets. The pretty little wood-sorrel plant of small yellow flowers, has three most beautiful, inverted, heart-shaped leaflets, radiating from the tip of the little leaf-stalk.
Leaflet of Wood-Sorrel.
In leaves like those of the maple we see the main veins radiating from a point at the top of the stalk. Such leaves are therefore much like the digitate kind, only they are not completely divided into separate leaflets.
Maple Leaf.
Sassafras leaves offer forms something different. On the same tree may be seen oval, two-lobed, and three-lobed leaves. Thus on one and the same plant, we see leaves strikingly different in form; yet the texture, the color, and the veining are exactly after the same pattern in them all, so that a sassafras leaf, whether oval or cleft, can at once be easily known.