Vegetable Teratology. Maxwell T. Masters
centre of six flowers, was placed a complete plant in miniature, having three leaves, from the axil of one of which proceeded a rudimentary flower. Mr. W. B. Jeffries also forwarded me a polyanthus (fig. 52) in which the peduncle was surmounted by a small plant, forming a crown above the ordinary flower-stalk, just as the crown of the pineapple surmounts that fruit. A similar instance was exhibited at the Scientific Committee of the Horticultural Society on July 11th, 1868, by Mr. Wilson Saunders; the species in this case was P. cortusoides. To Mr. R. Dean I am indebted for a similar proliferous cyclamen, which seems similar to one mentioned by Schlechtendal.[108] This author alludes to an analogous circumstance in the inflorescence of Cytisus nigricans, where, however, the change was not so great as in the preceding cases. The instances just cited all occur in plants having an indefinite form of inflorescence; but the production of a tuft of leaves or of a leafy shoot above or beyond the inflorescence is not confined to plants with this habit of growth, for Jacquin figures and describes an instance of this nature in the cymose flower-stems of a Sempervivum. "Hi racemi," says he, "ultra flores producuntur in ramos, foliosos duo bifidos qui tandem trium unciarum longitudinem adepti fuerunt."[109]
Fig. 52.—Inflorescence of Polyanthus, bearing a tuft of leaves at the top of the scape intermixed with the flowers.
Median floral prolification of the inflorescence, wherein a new inflorescence projects beyond the primary one, is not uncommon in plants having their flowers arranged in close heads or umbels, as in the common wild celery and other Umbelliferæ.[110] I have also met with it in Trifolium repens, in the umbellate variety of the common primrose, and in the scarlet geranium. Engelmann cites it in Triticum repens, Roëper in Euphorbia palustris.[111]
Lateral foliar prolification of the inflorescence is of more common occurrence than the preceding. I have met with it, amongst other plants, frequently in Brassica oleracea, Pelargonium zonale, Scabiosa, Bellis, and many other composites, also in Leguminosæ, e.g. Lupinus, Trifolium, Coronilla, &c. Prof. Oliver forwarded me a specimen of Euphorbia geniculata in which, in addition to other changes, there was a series of stalked buds bearing tufts of green scales, but without any trace of stamens or pistil; these adventitious buds occurred within the ordinary involucre of the plant, between it and the stamens. The pistil was unaffected in some cases, while in some others it was entirely wanting, the gynophore being surmounted by a cup-like involucre, divided into three acutely pointed lobes, each with a midrib; these encircled a series of stalked involucels, as before, and among which were scattered a few stamens, some perfect, others partially frondescent.
In a specimen of Scrophularia nodosa examined by me one of the lateral buds on each of the cymes was represented, not by a flower, but by a tuft of leaves, the other buds being unchanged. As the inflorescence was much contracted in size, the appearance of the whole plant was greatly changed.
Many of the instances of so-called viviparous plants, e.g., Polygonum viviparum, may be cited under this head.[112] Many species of Allium, Lilium, Saxifraga, Begonia, Achimenes, normally produce leaf-buds or bulbs in the inflorescence; so, too, leafy shoots are sometimes found in Alisma natans, Juncus uliginosus, Chlorophytum Sternbergianum, &c. As an accidental occurrence, a similar thing has been noticed in Lychnis coronaria, Phaius grandifolius, Oncidium cebolleta, Epidendrum elongatum,[113] &c. &c.
Here, too, may be mentioned those cases wherein a leaf-bud is found upon the surface of the so-called inferior ovary; generally a leaf only is found, but a leaf-bud may also originate in this situation, and in either case the inference is that the ovary is, in part at least, made of the dilated and hollowed axis. Leaves may occasionally be found in this way on the so-called calyx-tube or on the inferior ovaries of roses, pears, apples, Pereskia, Cratægus tanacetifolia, &c.
The fruits of Opuntia Salmania and of O. fragilis ('Bull. Soc. Bot. France,' vol. i, p. 306; vol. v, p. 115) have been observed to form small fruit-like branches around their summits. This circumstance is more fully treated of in the succeeding chapter relating to Heterotaxy.
Lateral floral prolification of the inflorescence.—This, which is termed by Engelmann Ecblastesis foliorum sub floralium,[114] is much the most common of all these deviations, and it is met with in every degree, from the presence of a single supernumerary flower in the axil of a bract to the existence of a small cluster or panicle of such flowers.
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