M. Wesmael[138] describes a very singular case of what appears to have been referable to axillary prolification in the flowers of Carex acuta. The rachillus is described as prolonged through the utricle by the side of the stigmas, bearing on its side a bract, then a secondary utricle, from the axil of which sprung a short stem surmounted by an ovary. Wigand, 'Flora,' 1856, mentions a similar change in Carex glauca. In this instance the base of the female inflorescence bore lateral spikes, which projected from the utricles; some of these adventitious spikes were female, others female below and male above, others, again, wholly male.
Fig. 65.—Flower of Nymphæa Lotus, var., showing axillary floral prolification. The section also shows the tuft of leaves that occupied the place of the ovary.
Various changes in the form and arrangement of the several floral whorls accompany axillary prolification; some of these affect the particular organ or organs implicated, and these only, while in other cases some other parts of the flower likewise undergo modification. The changes most commonly met with are such as may be classed under Goethe's theory of retrograde metamorphosis; for instance, if a supplementary bud be developed in the axil of a sepal, that sepal is likely to be more than ordinarily leaf-like in appearance. The dislocation of the affected sepal from its fellows is a very frequent occurrence; in cases of this kind the detached sepal is placed below the others, thus approximating, in position as well as in function, to the bracts. In some of the instances of proliferous pears, on which I shall have occasion to comment, the sepals are described as sharing in the succulent character of the fruit.
The petals, under such circumstances, often exist in the guise of sepals or of small leaves; and instances are recorded wherein the place of the calyx and corolla was supplied by a succession of overlapping green scales, from the axils of which the new buds arose. M. Germain de Saint Pierre records such a case in Trifolium repens, wherein the calyx and corolla were replaced by overlapping scales, in the axils of each one of which arose a flower; above there was a row of stamens, and in the centre a pistil in the guise of a trifoliate leaf.[139] Such instances seem to afford an extreme degree of a more common change, viz., the diminished size and contracted appearance of the sepals and petals when affected with axillary prolification. They have also a close relationship to such developments as we see in the wheat-ear carnation, in certain species of the genus Mæsa and others, wherein the calyx is repeated over and again, to the partial or complete suppression of the other parts of the flower. All these cases may be in part explained by the operation of the principle of compensation.
So far as the andrœcium is concerned, the stamens either remain unaltered, or they are present in a more or less petal-like condition; but it far more frequently happens that the stamens are entirely suppressed, the adventitious bud supplying their place; thus was it in the Dianthus represented in the adjoining woodcut, fig. 66, where the stamens were entirely absent, and their places supplied by flower-bearing branches. This Dianthus has the more interest from its similarity to the one described by Goethe, Metam. der Pflanzen, cap. 16, sect. 105; but in that instance median prolification also existed. For my specimens I am indebted to Mr. T. Moore.
Fig. 66.—Flower of Dianthus sp., calyx removed; petals turned down so as to show the stalked flower-buds springing from their axils.