[218.] Determinate Inflorescence is that in which the flowers are from terminal buds. The simplest case is that of a solitary terminal flower, as in Fig. [210]. This stops the growth of the stem; for its terminal bud, becoming a blossom, can no more lengthen in the manner of a leaf-bud. Any further growth must be from axillary buds developing into branches. If such branches are leafy shoots, at length terminated by single blossoms, the inflorescence still consists of solitary flowers at the summit of stem and branches. But if the flowering branches bear only bracts in place of ordinary leaves, the result is the kind of flower-cluster called
[219.] A Cyme. This is commonly a flat-topped or convex flower-cluster, like a corymb, only the blossoms are from terminal buds. Fig. [211] illustrates the simplest cyme in a plant with opposite leaves, namely, with three flowers. The middle flower, a, terminates the stem; the two others, b b, terminate branches, one from the axil of each of the uppermost leaves; and being later than the middle one, the flowering proceeds from the centre outwards, or is Centrifugal. This is the opposite of the indeterminate mode, or that where all the flower-buds are axillary. If flowering branches appear from the axils below, the lower ones are the later, so that the order of blossoming continues centrifugal or, which is the same thing, descending, as in Fig. [213], making a sort of reversed raceme or false raceme,—a kind of cluster which is to the true raceme just what the flat cyme is to the corymb.
Fig. 213. Diagram of a simple cyme in which the axis lengthens, so as to take the form of a raceme.
220. Wherever there are bracts or leaves, buds may be produced from their axils and appear as flowers. Fig. [212] represents the case where the branches, b b, of Fig. [211], each with a pair of small leaves or bracts about their middle, have branched again, and produced the branchlets and flowers c c, on each side. It is the continued repetition of this which forms the full or compound cyme, such as that of the Laurestinus, Hobble-bush, Dogwood, and Hydrangea (Fig. [214]).
Fig. 214. Compound cyme of Hydrangea arborescens, with neutral enlarged flowers round the circumference.
[221.] A Fascicle (meaning a bundle), like that of the Sweet William and Lychnis of the gardens, is only a cyme with the flowers much crowded.