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THE FLORAL CALENDAR.
BY PBOFESSOB JAMES BHOAD3.
(THE OBCHIs-LIKE BUTTEBWOBT.)
Botanical Characteristics of the genua:— Class, Dianbria; order, Monoqynia. Calyx 2lipped, upper lip S-cleft, lower, 2-cUft; corol. 1pelalled inferior, ringent, spurred at the bate; throat contracted; stamens and style short; stigma 1-lipped, covering the anther; capsule 1-celled, many-seeded, receptacle of the seed central.
The Pinguiculas or Butterworts, are a tribe of very interesting little plants. They are very easy of cultivation, but some of them, from their beauty and liveliness, would be well worth all the trouble they might give even were they less so. Few of them are, however,
moss and lumps of peat are the chief ingredients of which the soil should be composed when they are cultivated in pots. If not grown in the Wardian case, but in the open room, they require copious and frequent supplies of water; if there is always some kept in the saucer in which the pot stands, so much the better. We have several species natives of North America, but they are much less ornamental than many of the exotic kinds. The Orchis-like species, an individual of which is represented in figure 1, is a native of the highlands of Mexico, and is, in this latitude, a half-hardy plant. The foliage, from its singularity of shape and arrangement, is almost as interesting as the flower. From the ground springs a truncated cone of small scale-like leaves lying one over another, like the scales of the strobiles of a Pine tree, but of a green colour and delicate texture. From the summit of this cone proceeds a tuft of large, glabrous, spatulate leaves, of entirely different appearance from the under ones, and spreading entirely over and beyond them.
Florists are often heard to speak of beautiful flowers as being hybrids. Thus, they call one class of roses the " Hybrid Perpetual," and the Blush-flowered Corn-flag is said to be a hybrid between the Gladiolus cardinalis and the G. blandus. A few remarks respecting the meaning of the term, and the method of hybridizing, may not be unacceptable to the readers of the Calendar, as at this season of the year they need little particular information about the treatment of their window plants, exoept to keep them as cool as possible without freezing them, and gradually, as cold weather approaches, to diminish the quantity of water supplied to them.
If we refer to a common dictionary for the meaning of hybrid, we will find it to be " mongrel; of different species," a definition which itself needs to be defined before it conveys the proper idea. Any new variety of plant, produced by the joint action of the fructifying organs of different plants of distinct varieties, is called a hybrid between those varieties. The process of mixing different kinds of plants by I hybridization is to me a very interesting one. It is entirely another thing from inoculation or grafting. These do not produce new kinds; they merely enable us to place upon a vigorous stock of inferior properties, a parasite of an approved variety of the same natural genus. The scion being protected and favoured, acquires, after a time, sufficient energy to usurp and apply to its own use the food which the roots and stem of the original stock convey to it. The natures, however, of both stock and shoot remain unchanged, each, if new plants be propagated from them, will produce after its own kind. Very different is the result of hybridization. Something new, and in many particulars unlike both, is always produced, and often something much more beautiful or more valuable than either. So varied and extensive have been the benefits resulting from this process, that many florists are almost ready to believe that no variation or improvement can be effected by other means. It has, for instance, been from time immemorial the generally received opinion that double flowers have been produced from single ones, by continued cultivation, and stimulation in rich, generous soils, something after the manner noticed in the Calendar for November, of the single wild rose becoming the parent of double garden roses. Some late writers deny that this is the case with any plants, and assert that single flowers cannot, by any system of cultivation, be made to produce double ones. They assert that stamens never change into petals; that the wild rose may be cultivated from generation to generation in the best soil and with the utmost care, and will still have but five petals, unless hybridization has taken place spontaneously or artificially. Without entering into an argument upon the subject, I may remark, that hardly two individual roses, of even the same variety, can be found, which have the same number of petals; and that this continual variation can hardly be attributed to a perpetual mixture of kinds. Any one, too, who will take the trouble carefully to dissect a common double garden rose, will find what seems to me undeniable evidence that stamens do change to petals; for he will sec them in every degree of change,—some with their filaments merely a little flattened, others with the whole filament and part of the anther changed into petal-like texture, and others which can only be distinguished from the outer petals by having a small portion of the anther unchanged, and adhering to one edge. It will, however, be admitted on all sides, that hybridization is much more prolific of new varieties than any other of the artifices of florists, and that, "however beautiful plants naturally are, there is no denying that they are doubly so when they come from the hands of the skilful hybridizer."
Some of the younger and more inexperienced of my readers may desire, that before I proceed to describe the process of producing hybrids, I should explain several of the botanical terms I necessarily use. All must have noticed within the coloured part of a flower, one or more long slender organs, generally attached to the base or receptacle of the different parts of the flower. These are the organs of fructification,—the stamens, and pistils. The latter spring from the centre, and the former are arranged around them. Vast numbers of plants have but one pistil, but a very large majority have five or more stamens. The lower part of the pistil is called the germ, and becomes, when fructification is achieved, the seed-vessel. The top of the pistil is the stigma, the surface of which shortly after the opening of the flower, becomes moist or viscous, so that the pollen, when it falls upon it, may adhere until it has effected its purpose of fertilizing the germ through the pores of the stigma and style; the latter term being applied to the part which connects the stigma and germ. The stamen consists of but two parts,—the anther or little sack at the top, and the filament or threadlike stalk which supports it and elevates it above the pistil. Within each anther is a quantity of fine dust, which is called pollen. This is the fructifying principle. About the same time that the stigma becomes moist, the anthers burst and cast their pollen upon it. If the anthers were removed before the pollen impregnated the pistil, the plant would be barren and produce no seed. It is upon a knowledge of this fact, that the hybridizer proceeds. He manages to have two plants, of different varieties, sometimes of different species, but always agreeing in certain natural characteristics, to bloom simultaneously. From the one which ho designs to produce seed he cuts out the stamens, as soon as the flower opens; on the other, he permits them to remain. As soon as the pistil of the one deprived of its stamens assumes the moistness, to which I before alluded, which it does in a few days after the expansion of the flower, he causes the pollen from the stamens of the other plant to fall upon it. This he does either by bringing the two flowers in contact, or by means of a fine camel's-hair pencil. The seed thus obtained when sown will produce a new variety, differing from both parents, and denominated in florist's language a hybrid between the two. It is requisite for the success of this artificial impregnation that the stamens to be removed, be cut away immediately upon the opening of the flower, and early in the morning, when the pollen is more moist and less readily scattered than at other times;—for, it is a well-ascertained fact, that an exceedingly small particle of the pollen from the anthers produced on any individual, will fertilize the
pistil of that individual sooner and more readily than a much larger quantity from another plant. This principle of everything preferring its own kind, is one of the wise ordinances of Providence, established without doubt, to prevent an indiscriminate mixture and too great variety of species and genera, and so effective is it, that with the exception of varieties of the game species, there have been, in the opinion of the accurate and observing De Candolle, but about forty wild crossings since the world began. One remarkable fact to be observed during the process of hybridization is, that the fecundation is effected more laboriously and less perfectly, than when the plant is allowed its natural course. If in crossing five or six pairs of blossoms, of different species of the same genus, the most expert operator has one to succeed, he may consider himself fortunate. And, in the successful instance, he will find that the number of fertile seeds is much smaller than they would have been had the fecundation been natural. The capsule of a common poppy is said usually to contain 2130 seeds, but when crossed with another kind of poppy it will seldom contain more than eight or ten good seeds. The time also in which the fructification is effected is much longer. This can be ascertained by the fading or falling of the corolla, or part usually called the flower. When the fructification is effected, and the embryo seeds are formed, all the parts of the flower except the germ, wither and fall off. The time at which this takes place varies in different species; but in all the corolla and other parts remain much longer when the blossom is under hybridization than when in its natural condition. This increase of time amounts in many cases to several days. That it is owing to retarded fecundation is evident from the fact, that if the experiment be entirely unsuccessful and fecundation is not effected at all, the blossom will remain still longer unfaded. I have sometimes fancied it almost to feel that it had not performed its part until the organs which it protects and cherishes had provided for the continuance of the species, and that, when this consummation was delayed, it husbanded i^ strength and resources for a correspondent lengthening of existence.
(OE HEDOE-HOG CACTUSES.)
This tribe of plants I mentioned among others in a previous article, as adapted for growing in close glass-cases. They are indeed peculiarly suited to the condition of the atmosphere under such circumstances; and their
smallness of size is a great recommendation where economy of room is so important. Their singular habit of growth, in sub-globose form, renders them objects of curiosity, and they are frequently kept as such. But their shyness of bloom in common rooms, has prevented them from being generally grown, for however curious, they have, when not in blossom, very little beauty. If, in the Wardian case, they would not bloom more frequently than they do in the room at large, I should be slow to recommend the readers of the Calendar to keep them. I have never cultivated them myself, in any way, and cannot therefore speak from my own experience, but I am informed by those who have, that most of them will bloom abundantly in the case, and that this is particularly the fact with the Echinocactut Ozygonus, the beautiful species represented by figure 2. I am told further, that it will also bloom freely
if kept in a window under cover of a common hand-glass. The glass covering is necessary to its perfect development, inasmuch as, like the rest of the Cactece, though requiring little moisture at the root, it will not do well without a considerable portion in the air. E. Oxygonus is a native of South Brazil. It is one of the most showy of its tribe, and at the same time one of the most free-flowering. The long trumpetshaped tube of the flower, is of a light green, and is nearly covered with long, red-brown, imbricated scales. The colour of the inside of the petals is deep red rose, of the outside pale rose, and they cncloso numerous bright yellow stamens and anthers. The whole forms an object exceedingly beautiful and delicate in appearance.
Zephyrs are whispering, whispering, whispering, Full blushing roses all hark what they say; Moonlight ii
glimmering, glimmering, glimmering, Rippling and quivering bright o'er the bay. Nightin