Polyanthus

“ The polyanthus section, which includes the Paper-white narcissus and sacred lily or Chinese joss-flower, are not hardy except with unusually good protection, and are, therefore, most suitable for growing indoors.
It is common to allow the hardy sorts to take care of themselves when once planted. ”

“ They are, however, very distinct on the one hand from the primrose (Primula vulgaris or acaulis) and polyanthus (Primula elatior) sections; and also from the P. sinensis section—the species with so many fine double and single varieties, much grown in our greenhouses, and which, of course, are not hardy. The hardy and distinct species to which I now allude are mostly from alpine habitats, of stunted but neat forms, widely distinct, and very beautiful. ”

“ Many sowings of good seed have been thrown away because it was not known that the Polyanthus partakes of the slow and irregular characteristics of this class of plants. As the seedlings become ready, lift them carefully and transplant into pans or boxes, from which a little later they may be moved to any secluded corner of the border, until in September they are put into flowering quarters. While in the seed-pans they must be kept moist, although excessive watering is to be avoided. Should the summer prove dry, they will also need water when in the open ground. ”

“ In the moist, shady places of your garden you may plant Primroses and Polyanthuses [48] in colonies, and leave them to grow into great clumps and to seed themselves. But the best of them, those that you want to increase, you must pull to pieces when they have done flowering, and plant out in a shady corner. When you take up a clump you will usually see that it divides easily into several plants. You need not be afraid to use a knife in some places. Our experience is that every bit will grow, provided it has a few roots and plenty of shade and moisture during the hot summer months. ”

“ Polyanthus, prepotency over cowslip. Polygoneae. Posoqueria fragrans. Potato. Poterium sanguisorba. Potts, heads of Anthornis melanura covered with pollen. Primrose, Chinese. Primula elatior. — grandiflora. — mollis. — officinalis. — scotica. — sinensis. measurements. early flowering of crossed. — veris (var. officinalis) . measurements. result of experiments. early flowering of crossed. seeds. self-fertility. prepotency of dark red polyanthus. Primulaceae. Pringlea. Proteaceae of Australia. ”

“ Its variety, with white flowers, is also ornamental. It is raised from seeds, which are sold in plenty in our seed-shops.
40. PRIMULA officinalis. COWSLIP. PRIMULA vulgaris. PRIMROSE. PRIMULA elatior. OXLIP. PRIMULA farinose. BIRD'S EYE.—All well known ornaments of numerous varieties, double and single. The third species is the parent of the celebrated Polyanthus. The last is also an interesting little plant with a purple flower. It grows best in bog earth.
41. ROSA rubiginosa. SWEET BRIAR.—This lovely and highly extolled shrub has long claimed a place in our gardens. ”

“ In regard to the fertility of Primula species there are several paradoxes. For example the long-styled varieties, apart from giants, are fertile with their own pollen, and for many years short-styled plants have not been used in most strains. Auriculas and Polyanthuses, on the contrary, are generally if not always bred from short-styled plants, as the florists have decided that the long-styled are inadmissible. ”

“ In most cases the extremely fluctuating colour of seedling plants is probably in chief part due to crosses between differently-coloured varieties during previous generations. It is almost certain that this is the case with the polyanthus and coloured primrose (Primula veris and vulgaris) , from their reciprocally dimorphic structure; [49] and these are plants which florists speak of as never coming true by seed: but if care be taken to prevent crossing, neither species is by any means very inconstant, in colour; thus I raised twenty-three plants from a purple primrose, fertilised by Mr. ”

“ On the return of spring, they feed upon the young shoots, and for a few weeks show themselves great enemies to horticulture. Their visits to our flower-gardens, paid very early in the morning, are attested by scattered buds of polyanthuses, which they attack and pull to pieces as soon as they begin to push from between the leaves. ”

“ Like the daisy tree, the poinsettia flowers on the young wood, and throws out fresh branches six to ten feet long, which can be cut back in January, when the beauty of the blossoms is gone and the foliage becomes an unsightly yellow and at length drops altogether. When seen growing in all their luxuriant and garish splendour, it is difficult to remember that it is the same plant that one has seen in a weakly and attenuated form in our English stove-houses, with one poor little flower-head at the end of a single stem imperfectly clad with sickly foliage. ”

“ L. Polyphyllus and its varieties are perennials, and they are splendid and vigorous-growing plants, with spikes of flowers from one foot to eighteen inches in length; L. nootkatensis is a handsome dwarf perennial, and L. arboreus, when trained against a wall, will attain six feet in height, and in sheltered situations it will grow with equal vigor trained as a bush tied to a stake; L. latifolius is a perennial from California, with very long spikes of blue flowers. All the species will thrive in common garden soil ”

“ Within the stigmas of many other flowers pollen-leaves were observed. The plant produces plenty of seed; and thirteen of the twenty-one lower flowers on one spike had formed large capsules.
We will now turn to some exotic genera. The pollinia of Pleurothallis frolifera and ligulata (?) have a minute caudicle, and mechanical aid is requisite to force the viscid matter from the under side of the rostellum into the anther, thus to catch the caudicles and remove the pollinia. ”

“ In the rock-garden at the edge of the copse the creeping evergreen Polygala chamæbuxus is quite at home in beds of peat among mossy boulders. Where it has the ground to itself, this neat little shrub makes close tufts only four inches or five inches high, its wiry branches being closely set with neat, dark-green, box-like leaves; though where it has to struggle for life among other low shrubs, as may often be seen in the Alps, the branches elongate, and will run bare for two feet or three feet to get the leafy end to the light. ”

“ Polymnia pyramidalis.—A free, bold, and tall plant, with somewhat of a sunflower habit, but withal very fine, and making a tall green growth by the end of July, before many other things used in this way begin to push. The leaves are not so large as those of the other species, and differ in shape, being nearly cordate; but the growth is vigorous, and the habit distinct. It pushes up a narrow pyramidal head of foliage to a height of nearly 10 ft. ”

“ Montagnæa heracleifolia (Polymnia grandis) .—This is second to no other plant for its dignified and finished effect in the flower-garden, forming a handsome shrub with large, opposite, much-divided, and elegantly-lobed leaves, which are often nearly 3 ft. long, presenting very striking and luxuriant masses of foliage. The stem and leaf-stalks are spotted with white, and the leaves when young are covered with a soft white down. Like most large soft-growing things in this way, it is best planted out in a young state, so as to ensure a fresh and unstinted growth. ”

“ Some plants are all the better the higher and larger they are grown; others must be started in a dwarf fresh state every year, or, if not, their foliage will not possess that pristine freshness which charms us when they are properly treated. A large plant of Polymnia grandis, for example, would, if placed in the open air in early summer, speedily become a far from attractive object, while a young plant of the same kind, put out on the same day, would soon produce and carry to the end of the season a mass of fresh and noble leaves. ”

“ In many cases cross-pollination is assured because the stamens and the pistils are in different flowers (diclinous) . Monœcious and diœcious plants may be pollinated by wind or insects, or other agents (Fig. 204) . They are usually wind-pollinated, although willows are often, if not mostly, insect-pollinated. The Indian corn is a monœcious plant. The staminate flowers are in a terminal panicle (tassel) . The pistillate flowers are in a dense spike (ear) , inclosed in a sheath or husk. Each “silk” is a style. Each pistillate flower produces a kernel of corn. ”

“ The pollen falls from the male spikes on the ears of the same plant, but also is easily blown on surrounding spikes. In order to get the required amount of seed it is necessary in our climate to encroach as little as possible upon free pollination, aiding the self-pollination, but taking no precautions against intercrossing. It is assumed that the choice of the best ears indicates the plants which have had the best pollen-parents as well as the best pistil parents, and that selection here, as in other cases, corrects the faults of free intercrossing. ”

“ The most important difference, however, was the inability to produce good pollen. The anthers of the mother species are, when open, thickly covered with a sticky powder, which is entirely lacking in the case of the roundheads. The anthers of the new form are dry, what little pollen there is is shriveled, for the greater part unfertile and entirely unfit for fertilization. The plant is purely feminine. Male or hermaphrodite specimens I never saw, though I have often cultivated hundreds of roundheads. ”

“ In order that fertile seed may be produced it is often necessary, and usually desirable, that the pollen which reaches the stigma should not belong to the same flower, but to a different flower of the same species; cross-pollination being the rule among seed plants, self-pollination the exception. To secure{83} the former, and to avoid the latter, many highly interesting devices are found, materially affecting the structure and development of flowers. ”

“ From clump to clump he flies, and through his help each one of the pale blue blooms is sure to get its food, each flower fertilized by the pollen of another.
Another beautiful provision is seen in the difference in size of the pollen grain of the two flowers, those of the high anthers being much larger than those from the lower anthers. These larger grains are intended for the high stigma, which they are sure of reaching, while those of smaller size, on the top of the tongue, which should happen to be wiped off on the high stigma, are too small to be effective for fertilization. ”

“ Nearly all trees or shrubs, seldom herbs, generally with latex. The leaves are scattered, and not infrequently lobed. The flowers are unisexual (monœcious or diœcious) and arranged in catkin- or capitulum-like, compound inflorescences. Perianth-leaves 2–6, generally 4, with an equal number of stamens opposite to them, as in the Nettles. The [354] ovary is 1–seldom 2-locular, and has 2 stigmas (it is thus formed from 2 carpels) seldom only one style with one stigma. One ovule in each loculus, more or less curved, and pendulous; micropyle directed upwards. Fruit usually a drupe. ”

“ In orchidaceous plants the pollen-grains are united into masses, or pollinia (fig. 78) , by means of viscid matter. In orchids each of the pollen-masses has a prolongation or stalk (caudicle) which adheres to a prolongation at the base of the anther (rostellum) by means of a viscid gland (retinaculum) which is either naked or covered. The term clinandrium is sometimes applied to the part of the column in orchids where the stamens are situated. In some orchids, as Cypripedium, the pollen has its ordinary character of separate grains. The number of pollinia varies ”

“ Pollination.—Grasses are generally wind-pollinated, though self-fertilization sometimes occurs. A few species, as we have seen, are monoecious or dioecious, while many are polygamous (having unisexual as well as bisexual flowers as in many members of the tribes Andropogoneae, fig. 18, and Paniceae) , and in these the male flower of a spikelet always blooms later than the hermaphrodite, so that its pollen can only effect cross-fertilization upon other spikelets in the same or another plant. ”

“ The seeds are surrounded by the perianth which finally becomes red and fleshy. There are 30 species.—Gnetum has opposite, lanceolate, pinnately-veined, leathery leaves. They are mostly climbers (Lianas) from Tropical Asia and America. The ♂-flowers have a tubular perianth, (formed from two median leaves) which surrounds a centrally-placed filament, bearing 2 anthers. In the ♀-flower there is a similar perianth, surrounding an ovule provided with 2 integuments. The perianth becomes fleshy and envelops the hard seed. 20 species. ”

“ In the mean while plenty of barren flowers are produced on a distinct root, on short straight stalks, from which they rise like little separate white bubbles, suddenly expanding when they reach the surface, and floating about in such abundance as to cover it entirely. Thus their pollen is scattered over the stigmas of the first-mentioned blossoms, whose stalks soon afterwards resume their spiral figure, and the fruit comes to maturity at the bottom of the water. ”

“ When the stigma is ready, an unopened anther from the desired flower is crushed on the finger nail or a knife blade, and the pollen is rubbed on the stigma by means of a tiny brush, the point of a knife blade, or a sliver of wood. The flower is again covered with the bag, which is allowed to remain for several days until all danger of other pollination is past. Care must be taken completely to cover the stigmatic surface with pollen, if possible. The seeds produced by a crossed flower produce hybrids, or plants having parents belonging to different varieties or species. ”