Vegetable Teratology / An Account of the Principal Deviations from the Usual Construction of Plants

by Maxwell T. Masters

Fig. 13.—Cheiranthus cheiri. Adhesion of petal to stamen and open carpel.

It is curious to notice how very rare it is for the calyx to adhere to the ovary in flowers where that organ is normally superior. The "calyx inferus" seems scarcely ever to become "calyx superus," while, on the other hand, the "calyx normaliter superus" frequently becomes inferior from detachment from, or from want of union with the surface of the ovary.

Adhesion of fruit to branch.—Of this Mr. Berkeley[40] cites an instance in a vegetable marrow (Cucumis), where a female flower had become confluent with the branch, at whose base it was placed, and also with two or more flowers at the upper part of the same branch, so as to make an oblique scar running down from the apex of the fruit to the branch.

Synanthy.—Adhesion of two or more flowers takes place in various ways; sometimes merely the stalks are united together, so that we have a single peduncle, bearing at its extremity two flowers placed in approximation very slightly adherent one to the other. In this manner I have seen three flowers of the vegetable marrow on a common stalk, the flowers themselves being only united at the extreme base. Occasionally cases may be met with wherein the pedicels of a stalked flower become adherent to the side of a sessile flower. I have noticed this commonly in Umbelliferæ. Union of this kind occurs frequently in the common cornel (Cornus), wherein one of the lower flowers becomes adherent to one of the upper ones. In De Candolle's 'Organographie Végétale,' Plates 14 and 15, are figured cases of fusion of the flower stems of the Hyacinth and of a Centaurea. In other cases the union involves not only the stalk but the flowers themselves; thus fusion of the flowers is a common accompaniment of fasciation, as was the case in the Campanula figured in the cut (fig. 14).

Fig. 14.—Synanthic flowers of Campanula medium.

Synanthy may take place without much derangement of the structure of either flower, or the union may be attended with abortion or suppression of some of the parts of one or both flowers. Occasionally this union is carried to such an extent that a bloom appears to be single, when it is, in reality, composed of two or more, the parts of which have become not only fused, but, as it were, thrust into and completely incorporated one with another, and in such a manner as to occupy the place of some parts of the flower which have been suppressed. It must not be overlooked that this adhesion of one flower to another is a very common occurrence under natural circumstances, as in Lonicera, in the common tomato, in Pomax, Opercularia, Symphyomyrtus, &c., while the large size of some of the cultivated sunflowers is in like manner due to the union of two or more flower-heads.

One of the simplest instances of synanthy is that mentioned by M. Duchartre,[41] in which two flowers of a hyacinth were united together simply by means of two segments of the perianth one from each flower. A similar occurrence has been cited by M. Gay in Narcissus chrysanthus. In like manner the blossoms of Fuchsias or Loniceras occasionally become adherent merely by their surface, without involving any other change in the conformation of the flowers. M. Maugin alludes to a case of this kind in Aristolochia Clematitis.[42]

But it is more usual for some of the organs to be suppressed, so that the number of existing parts is less than would be the case in two or more uncombined flowers. A few illustrations will exemplify this. In two flowers of Matthiola incana, that I observed to be joined together, there were eight sepals, eight petals, and ten perfect stamens, eight long and two short, instead of twelve. Closer examination showed that the point of union between the two flowers occurred just where, under ordinary circumstances, the two short stamens would be. In this instance but little suppression had occurred. In similar flowers of Narcissus incomparabilis I remarked a ten-parted perianth, ten stamens within a single cup, two styles, and a five-celled ovary. Here, then, it would appear that two segments of the perianth, two stamens, and one carpel were suppressed. In a Polyanthus there were nine sepals, nine petals, nine stamens, and a double ovary.