Occasionally the laminar portions of the leaf are completely wanting, leaving only the main ribs, as in the case of Berberis, while the adjoining figure (fig. 215) represents an instance of a cabbage wherein the innermost leaves are represented by thick fleshy cylindrical bodies corresponding to the midribs of the ordinary leaves. There is in cultivation a variety of the cabbage which constantly presents this peculiarity.
Fig. 215.—Inner leaves of cabbage reduced to their midribs.
The suppression of one or more leaflets of a compound leaf has already been referred to at p. 396.
Abortion of the perianth, calyx, and corolla.—Illustrations of partial development in these organs are not rare, under ordinary circumstances, as for instance the "obsolete" calyx of Umbellifers. In the cauliflower the branches of the inflorescence are contracted in length, while their succulence is much increased; at their extremities they bear crowds of imperfect flowers, in which the calyx only is visible, and that only in a rudimentary and partially developed condition. Imperfect development of the whole or of some of the constituent parts is more common in the case of the corolla than in that of the calyx. In Arenaria serpyllifolia the petals, especially in autumn, are only one fourth the length of the sepals. Anagallis phœnicea, Honckenya peploides, Arabis alpina, Ranunculus auricomus, Rubus fruticosus, and Geranium columbinum, also frequently afford illustrations of this circumstance.
Fig. 216.—Abortion of four out of five petals, Viola tricolor, side and front views.
At fig. 216 is represented a pansy in which four of the five petals were very small and colourless, while the lower spurred petal was of the usual size and colour. In this flower the stamens and pistils were wholly suppressed, and the flower-stalk, instead of being bent near the flower, retained its primary straight direction. Similar atrophic conditions of the corolla occur habitually among Violaceæ.