Thus, in a phanerogam, the sepals, petals, stamens and foliage-leaves all come under the category leaf, though some are parts of the perianth, others are spore-bearing organs (sporophylls), and others carry on nutritive processes.
It has pale-purple flowers, rarely more than three in number; the perianth is funnel-shaped, and produced below into a long slender tube, in the upper part of which the six stamens are inserted.
The conformation of those flowers a consists essentially in the pres- ' 'A B ence of a six-parted perianth, the three outer segments of which correspond to a calyx, the three inner ones to a corolla.
These segments spring apparently from the top of the ovary - the real explanation, however, being that the end of the flower-stalk or "thalamus," as it grows, becomes dilated into a sort of cup or tube enclosing and indeed closely adhering to the ovary, so that the latter organ appears to be beneath the perianth instead of above it as in a lily, an appearance which has given origin to the term "inferior ovary."
Within the perianth, and springing from its sides, or apparently from the top of the ovary, are six stamens whose anthers contain pulverulent pollen-grains.
Described, but with the ovules on the walls of the cavity (not in its axis or centre), a six-parted perianth, a stamen or stamens and stigmas.
The main distinguishing features consist in the fact that one of the inner pieces of the perianth becomes in course of its growth much larger than the rest, and usually different in colour, texture and form.
It would appear, then, that the orchid flower differs from the more general monocotyledonous type in the irregularity of the perianth, in the suppression of five out of six stamens, and in the union of the one stamen and the stigmas.
Other common modifications arise from the union of certain parts of the perianth to each other, and from the varied and often very remarkable outgrowths from the lip. These modifications are associated with the structure and habits of insects and their visits to the flowers.
The remaining parts of the perianth are very much smaller, and commonly are so arranged as to form a hood overarching the "column."
Flower with Perianth removed.
A small group of Australian genera closely approach the order Juncaceae in having small crowded flowers with a scarious or membranous perianth; they include Xanthorrhoea (grass-tree or blackboy) and Kingia, arborescent plants with an erect woody stem crowned with a tuft of long stiff narrow leaves, from the centre of which rises a tall dense flower spike or a number of stalked flower-heads; this group has been included in Juncaceae, from which it is doubtfully distinguished only by the absence of the long twisted stigmas which characterize the true rushes.
It resembles Juncaceae in the general plan of the flower, which, however, has become much more elaborate and varied in the form and colour of its perianth in association with transmission of pollen by insect agency; a link between the two orders is found in the group of Australian genera referred to above under Asphodeloideae.
The flowers are hermaphrodite and regular, with the same number and arrangement of parts as in the order Liliaceae, from which they differ in the inconspicuous membranous character of the perianth, the absence of honey or smell, and the brushlike stigmas with long papillae-adaptations to wind-pollination as contrasted with the methods of pollination by insect agency, which characterize the Liliaceae.
From the margin springs a perianth of four short lobes.
The flowers are regular, with a perianth springing from above the ovary, tubular below, with spreading segments and a central corona; the six stamens are inserted within the tube.
Of this group the most striking one perhaps is N, bicolor, which has the perianth almost white and the corona deep yellow; it yields a number of varieties, some of the best known being Empress, Horsfieldi, Grandee, Ellen Willmott, Victoria, Weardale Perfection, &c. N.
They admit of being forced into early bloom, like the hyacinth and tulip. They vary with a white, creamy or yellow perianth, and a yellow, lemon, primrose or white cup or coronet; and, being richly fragrant, they are general favourites amongst spring flowers.
Poeticus), in which the perianth is large, spreading and conspicuous, and the corona very small and shallow.
The white perianth is six-parted, the outer three segments being larger and more convex than the inner series.
Candidum; an open form with spreading perianth leaves, e.g.
One of the most important of the properties of a fine florists' tulip is that the cup should form, when expanded, from half to a third of a hollow ball, the six divisions of the perianth being broad at the ends, and smooth at the edges, so that the divisions may scarcely show on indenture.
These form the perianth and are in one series, when the flower is termed monochlamydeous, or in two series (dichlamydeous).
The seven series of Monocotyledons represent a sequence beginning with the most complicated epigynous orders, such as Orchideae and Scitamineae, and passing through the petaloid hypogynous orders (series Coronarieae) of which Liliaceae is the representative to Juncaceae and the palms (series Calycinae) where the perianth Ioses its petaloid character and thence to the Aroids, screw-pines and albuminous Dicotyledons the cotyledons act as the absorbents of the reserve-food of the seed and are commonly brought above ground (epigeal), either withdrawn from the seed-coat or carrying it upon them, and then they serve as the first green organs of the plant.
The petaloid perianth consists of two series, each with three members, which are joined below into a longer or shorter tube, followed by one whorl of three stamens; the inferior ovary is three-celled and contains numerous ovules on an axile placenta; the style is branched and the branches are often petaloid.
B, b', Upper and lower membranous spathe-like bracts; c, Tube of perianth; d, Ovary; e, Style; f, Stigmas.
The flower has in rare cases a perianth of six scale-like leaves arranged in two whorls, and thus conforming to the common monocotyledonous type of flower.
Is represented in Britain by several species in boggy land; they are small tufted herbs with cottony heads due to the numerous hair-like bristles which take the place of the perianth and become much elongated in the fruiting stage.
This structure was formerly regarded as pointing to the fusion of two organs, and the pale was considered by Robert Brown to represent two portions soldered together of a trimerous perianth - whorl, the third portion being the " lower pale."
The perianth is represented by very rudimentary, small, fleshy scales arising below the ovary, called lodicules; they are elongated FIG.
R 5), it will be seen to differ in the absence of the outer row and the posterior member of the inner row of the perianth-leaves, of the whole inner row of stamens, and of the two lateral carpels, FIG.
Whilst the remaining members of the perianth are in a rudimentary condition.
D, Outer row of perianth leaves.
Flowers monoecious or dioecious, unisexual, without a perianth, often in the form of cones, but never terminal on the main stem.
The presence of a perianth is a feature suggestive of an approach to the floral structure of Angiosperms; the prolongation of the integument furnishes the flowers with a substitute for a stigma and style.
A single male flower consists of an axis enclosed at the base by an inconspicuous perianth formed of two concrescent leaves and terminating in two, or as many as eight, shortly stalked or sessile anthers.
The female flower is enveloped in a closely fitting sac-like investment, which must be regarded as a perianth; within this is an orthotropous ovule surrounded by a single integument prolonged upwards as a beak-like micropyle.
The flower may be described as a bud bearing a pair of leaves which become fused and constitute a perianth, the apex of the shoot forming an ovule.
In function the perianth may be compared with a unilocular ovary containing a single ovule; the projecting integument, which at the time of pollination secretes a drop of liquid, serves the same purpose as the style and stigma of an angiosperm.
After fertilization, some of the uppermost bracts below each flower become red and fleshy; the perianth develops into a woody shell, while the integument remains membranous.
A male flower consists of a single angular perianth, through the open apex of which the flower-axis projects as a slender column terminating in two anthers.
The whole flower may be looked upon as an adventitious bud bearing two pairs of leaves; each pair becomes concrescent and forms a perianth, the apex of the shoot being converted into an orthotropous ovule.
The fleshy outer portion of the seed is formed from the outer perianth, the woody shell being derived from the inner perianth.
Each cone consists of an axis, on which numerous broad and thin bracts are arranged in regular rows; in the axil of each bract occurs a single flower; a male flower is enclosed by two opposite pairs of leaves, forming a perianth surrounding a central sterile ovule encircled by a ring of stamens united below, but free distally as short filaments, each of which terminates in a trilocular anther.
Sometimes, as usually in monocotyledons, the calyx and corolla are similar; in such cases the term perianth, or perigone, is applied.
Thus, in the tulip, crocus, lily, speak of the parts of the perianth, in place of corolla, although in these plants there is an outer whorl (calyx), of three parts, and an inner (corolla), of a similar number, alternating with them.
- Monochlamydeous (apetalous) flower of Goosefoot (Chenopodium), consisting of a single perianth (calyx) of five parts, enclosing five stamens, which are opposite the divisions of the perianth, owing to the absence of the petals.
Coloured hairs are seen on the petals of Menyanthes, and on the segments of the perianth of Iris.
When the perianth (p) expands, the filaments are thrown out with force as at a, so as to scatter the pollen.
The ovary, three-celled at first, but becoming one-celled and one-seeded by abortion, is surmounted by an inconspicuous perianth with six small teeth.
The purple flower, which blooms late in autumn, is very similar to that of the common spring crocus, and the stigmas, which are protruded from the perianth, are of a characteristic orange-red colour.
The perianth consists of five or six oblong greenish lobes, within which is found a tuft, consisting of a large number of stamens, each of which has a very short filament and an oblong two-lobed anther bursting longitudinally, and surmounted by an oblong lobe, which is the projecting end of the connective.