Some of the above are probably cases of mere virescence rather than of phyllody. For further illustrations, references to authorities, &c., see under Chloranthy, Virescence, Prolification, &c.
Phyllody of the ovules.—Pending the settlement of the existing differences of opinion with reference to the morphological nature of the ovule and its component parts, much interest attaches to the malformations to which they are occasionally subject. Considered purely in a teratological point of view, it seems clear that the ovular coats are usually, if not always, of foliar nature, while the central nucleus is an axial organ; but if this be so there still remains the question whether the leafy coats of the ovule are processes of the carpel itself, or distinct independent formations, like the scales of a leaf-bud; as to this latter point, the evidence is at present very conflicting. Prof. Al. Braun, who has devoted much attention to the subject, describes and figures ovules of Nigella and Adonis, wherein the outer coat of the ovule was converted into a leafy, lobed mass, like the ordinary leaves, and these he considers to be a portion, not of the carpel, but of the ovular bud; he, however, hesitates to pronounce an opinion on the nature of the pedicel of the ovule. In Primulaceæ, wherein ovular changes are very common, the leafy coat of the ovule would seem, from the nature of the placenta, to be independent of the carpel. Morren, who studied the changes in the ovules of Primula sinensis, applied the term lepyrophylly (λεπυρον, a scale) to the foliaceous condition of the testa in this plant. Unger[267] describes a series of malformations in Primula sinensis, consisting chiefly of reversions of the part of the flower to leaves. The carpels were entirely absent in this case, and the place of the free central placenta was occupied by a circle of leaves, sometimes bearing imperfect ovules on their edges. An instance of a similar kind has been described by A. de Candolle.[268]
In these flowers the placenta seemed to be composed of several funiculi soldered together, and bearing imperfect ovules. In other cases no traces of ovules are visible, but the funiculi are in a foliaceous condition. Moquin also alludes to a case of the same nature in Cortusa Mathioli, in which the funiculi bore little rounded leaves. Brongniart has described some malformations of Primula sinensis in which the ovules were transformed wholly or partially into small leaves with three to five lobes.[269] Dr. Marchand[270] mentions similar changes in Anagallis arvensis and Lonicera Periclymenum.
Cramer[271] figures ovules of Primula sinensis in the form of stalked leaves, often becoming infolded at the margins, and giving origin to a small nucleus on their inner surface.
M. Tassi[272] records an instance in Symphytum officinale wherein the ovules were replaced by two small linear leaves arising entirely from the axis, and not from the carpels.
In most of the foregoing illustrations the foliar portion of the ovule must have been independent of the carpel; this independence is less manifest, though probably as real in the cases now to be mentioned. In Sinapis and in Brassica oleracea foliaceous ovules may occasionally be seen, attached to the placenta by long stalks. No trace of the nucleus is visible in these specimens.
Fig. 140.—Sinapis, replum and ovules; the dotted line shows the position of the carpels.
Griffith, in alluding to a similar case in Sinapis,[273] describes the ovules as foliaceous, and having their backs turned away from the axis, the raphe being next to the axis and representing the midrib the funicle corresponding to the petiole. The outer tegument of the ovule, according to Griffith, is a leaf united along its margins, but always more or less open at its apex. No inversion can, therefore, really take place in anatropous ovules, but the blade of the leaf is bent back on the funicle, with which its margins also cohere.