Plants ought, in all cases where practicable, to be gathered when dry; or, if moist with rain or dew when gathered, they ought to be exposed to the atmosphere of a dry room for an hour or two previous to being put into papers. For the conveyance of specimens a tin box, called a vasculum, is used, which prevents the plants withering during a long journey, and otherwise protects them. Some of our readers may not think the japanned tin vasculum a very elegant accoutrement, but it is quite usual for ladies to carry such along the streets of Modern Athens, where, through the labors of Professor Balfour and others, botany has, of late years, become of high repute as a feminine accomplishment.
In proceeding to dry the plants, procure a quantity of soft blotting-paper. Four or five sheets are to be laid down on the table (each folded within the other, as in a ream), and on the uppermost one the specimen is to be laid. Spread it out carefully, separating the branches and leaves so that they do not overlap; and after this is done, a slip of paper or "label" put beside the specimen, indicating its botanical name, the locality where collected, and the date when; then another four or five sheets, folded as before, are to be laid over the plant. On the surface of this latter layer of paper, another specimen or specimens may be spread—an additional layer of four or five sheets being placed over them—and so on until all the specimens collected are spread out. A board of the same size as the paper is to be placed above the uppermost sheet, and on the top of that a heavy weight, fifty or sixty pounds. A bundle of large volumes will serve the purpose of a weight, if no better is at hand. Some recommend a screw-press for pressing the plants, instead of a weight; but presses of all kinds are objectionable, as the shrinking of the plants renders the pressure unequal from the want of elasticity, which is so easily attained by means of an ordinary weight. After the specimens have been allowed to stand in this manner twenty-four hours or so, they should be taken carefully out; such leaves as are disarranged should be spread out properly, and the whole put into dry paper, in the same way as in the previous operation. The moist paper from which they are taken should be spread before the fire to dry; it will be ready for use another time. The plants are to be supplied with dry paper, in this manner, once every twenty-four hours, until they have become quite dry, when they may be taken out and put apart in single sheets of gray paper.
The operation of drying the specimens has been here described, but that of mounting them on white paper is equally important. Gum Arabic is generally used for this purpose, but it is very bad; does not adhere sufficiently, and thus allows the specimens to spring off from the sheets. Fine glue, prepared in a very thin state, is the best material for fixing the plants. The melted glue should, when very hot, be spread over the specimen carefully with a brush, a sheet of dirty absorbent paper lying beneath the specimen to prevent the glue soiling anything, and then the specimen is to be put down upon the sheet of white paper previously laid out for its reception. A towel is then taken to press the different branches or leaves gently down upon the surface of the paper. After this is done, a few sheets of drying paper are to be laid over the specimen, and on the top of this another sheet of white paper for the reception of another glued specimen, and so on until all are completed. A board is then to be placed over the whole, and a weight, in order to press all parts of the plants equally to the sheets of paper, until they are made firm by the drying of the glue. After the specimens have stood in this manner a few hours, they are to be taken out, their names, localities, and dates written at the bottom of the sheet, and the whole arranged in such manner as the possessor may think proper. Any refractory stems or branches that have sprung up from the paper in spite of the glue, may be fastened down by slips of gummed paper. The marginal portion of postage-stamp sheets supplies these to those who can obtain them in sufficient quantity.
The plants of each genus are to be put together inside of a double sheet of paper, with their generic name written at the bottom of the sheet upon the outside at the left hand corner; for instance, the pansy, the sweet violet, the dog violet, the yellow mountain violet, &c., are all to be put inside of one double sheet, the generic name "VIOLA" being written upon the corner of it. This is to facilitate references.
We now proceed to point out what spring flowers are likely to reward the exertions of those who go in search of them among the woods and fields. And first of all the primrose and the cowslip demand attention as general favorites. The wild plant, with its modest flower of pale yellow hue (which has given rise to the name of a tint known as primrose yellow), is probably familiar to every one, but it may not be so well known that the gay polyanthus of our florists, and the rich double-flowered primroses of every hue which decorate our gardens, all owe their existence to the wild plant as their original stock. The cowslip, although local in its geographical distribution, is abundant in many localities, and is associated right pleasantly with cowslip wine. Beneath the hedges in early spring-time there is a pretty little plant which seldom catches the eye of the passer-by; it is aptly styled the "gloryless," for its little flowers are of greenish-yellow hue, and so small as to be inconspicuous to any one save the botanical explorer. When examined, however, it is an object of great, though simple beauty. It sends up a delicate stem, which bears a little rosette of divided leaves, and from amidst this rises the flower-stalk, pale and slender, bearing on its summit a compact head of a few tiny showless flowers. Its botanical name is Adoxa Moschatellina.
It is summer time before the buttercups begem the pastures; but one member of the family already welcomes us by hedge-rows; it is the Lesser Celandine of Wordsworth, which received a special favor from his pen in the dedication of a pretty little poem. The Lesser Celandine (Ranunculus Ficaria) grows abundantly on wet shady banks, and produces a profusion of its bright glossy golden flowers, which, in fading, assume a pure white hue. This ranks as one of the economical plants of Britain; and humble as it is, it has been brought forward as a substitute for that unfortunate vegetable, the potato. Plants of the Lesser Celandine, raised from roots which had been gathered in Silesia by the Rev. Mr. Wade in 1848, were grown in the Edinburgh Botanic Garden, and exhibited by Mr. M'Nab, the curator of the garden, to the Botanical Society. These roots had been exposed over a large extent of country in Austria by heavy rains, and the common people gathered them and used them as an article of food. Their sudden appearance gave rise to various conjectures as to their nature and origin, and in the Austrian journals they were spoken of as if they had fallen from the sky. The "small bodies" (roots) were used as peas by the inhabitants. Either in a dried state, or when fresh, they are found, on boiling, to be very amylaceous; that is, they contain much starchy matter. There is no acridity in the roots even in a fresh state, which is a remarkable fact when we take into consideration the acrid and poisonous nature of the entire race of plants allied to it in structure, viz., the Ranunculaceæ, to which order it belongs. For instance, one of these plants, the Indian Aconite, is thus spoken of by Professor Balfour:—
"The root of the plant possesses extreme acrimony, and very marked narcotic properties. It is said to be the most poisonous of the genus, and as such has been employed in India. Wallich says that in the Turraye, or low forest-lands which skirt the approach to Nipal, and among the lower range of hills, especially at a place called Hetounra, quantities of the bruised root were thrown into wells and reservoirs, for the purpose of poisoning our men and cattle. By the vigilant precaution of our troops, however, these nefarious designs were providentially frustrated. In the northern parts of Hindoostan, arrows poisoned with the root are used for destroying tigers. The root, according to Rayle, is sent down into the plains, and used in the cure of chronic rheumatism, under the name of Metha tellia. Roots, apparently of this plant, were sent by Dr. Christison from Madras under the name of Nabee. Pereira made a series of experiments on the roots which had been kept for ten years, and still retained their poisonous properties. The roots were administered to animals in the form of a powder, and spirituous and watery extract. The spirituous extract was the most energetic, the effects produced being difficulty of breathing, weakness, and subsequent paralysis, which generally showed itself first in the posterior extremities, vertigo, convulsions, dilatation of the pupil, and death apparently from asphyxia."
One grain of the alcoholic extract killed a rabbit in nine and a half minutes, and two grains introduced into the jugular vein of a strong dog caused death in three minutes.
This is the general character of the crowfoots, and they are indeed the most destructive cattle poisons that infect our pastures; it is a curious fact, therefore, that one of them should be so harmless and so nutritious as we have seen the Lesser Celandine to be; and a still more curious fact that Linnæus, the father of naturalists, should have thought that agriculturists should endeavor to extirpate this pretty flower, not only as acrid and poisonous, but as injurious to all plants growing near it.