A Compound Leaf is one which is divided into leaflets, as in the Wild Rose, Pink Clover, and Travellers’ Joy (Pl. XXXI., also Fig. 2).
A Much-divided Leaf is one which is several times divided into leaflets (Fig. 3).
The Axil of a leaf is the upper angle formed by a leaf or leaf-stalk and the stem.
Flowers which grow from the axils of the leaves are said to be Axillary.
A cluster in which the flowers are arranged—each on its own stalk—along the sides of a common stem or stalk is called a Raceme. (See Cardinal-flower, Pl. LXXXIII.; Shin-leaf, Pl. XVIII.)
A cluster in which the flower-stalks all spring from apparently the same point, as in the Milkweeds, somewhat suggesting the spreading ribs of an umbrella, is called an Umbel (Pl. LXXXI.).
A cluster which is formed of a number of small umbels, all of the stalks of which start from apparently the same point, is called a Compound Umbel. (See Wild Carrot, Pl. XXVIII.)
A close, circular flower-cluster, like that of Pink Clover or Dandelion, is called a Head. (See Oswego Tea, Pl. LXXXII.; Sunflower, Pl. LVII.)
A flower-cluster along the lengthened axis of which the flowers are sessile or closely set is called a Spike. (See Vervain, Pl. XCII.; Mullein, Pl. LI.)
A Spadix is a fleshy spike or head, with small and often imperfect flowers, as in the Jack-in-the-Pulpit, and Skunk Cabbage (Pls. CII. and CIV., also Fig. 4).