This section of the book is from "The Complete Herbalist" by Dr. O. Phelps Brown. Also available from Amazon: The Complete Herbalist: The People Their Own Physicians By The Use Of Nature's Remedies.
Plants sometimes distil or secrete medicinal or nutritive fluids, which are contained in convenient receptacles. Such plants invariably grow far from the haunts of men, away from the course of streams or vicinity of ponds. Whose ordination is it that such plants have such a habitude? It is that Providence who, in his bountiful beneficence, places them where the traveler may not die of thirst or disease on his way of discovery. This is most beautifully illustrated in the Nepenthes distillatoria in which the leaves terminate in a most singular manner, forming a sort of urn or vase, surmounted by a cover which opens and shuts as occasion requires. This vessel is suspended at the extremity of a thread-like appendage to a winged petiole, which would seem to be altogether unfit to support it. An officer of marines writes as follows: "Three days after my arrival at Madagascar I lost myself during a short excursion into the interior and was overtaken with an excessive lassitude, accompanied with a devouring thirst. After a long walk I was on the point of yielding to despair when I perceived close to me, suspended to leaves, some small vases, somewhat like those used to preserve fresh water. I began to think I was under one of those hallucinations by which the sick are often visited in fever, when the refreshing draught seems to fly from their parched lips. I approached it, however, with some hesitation, threw a rapid glance at the pitchers: judge of my happiness when I found them filled with a pure and transparent liquid. The draught I partook gave me the best idea I have realized of the nectar served at the table of the gods." Plants of such description become extinct if civilization approaches their domain.
Plants have attributes other than medical which are of interest to the general reader besides the botanist.
In many instances there seems to be a striking affinity between the herbal and animal kingdom, and other instances of the repelling character. For instance, a most remarkable instance of irritability by contact is that exhibited by the "Venus's Fly-Trap," Dionaea muscipula, a native of Canada, and nearly allied to the common "Sun-Dew" of the British commons. Its flowers have nothing remarkable about them, except that their petals roll up when they are about to decay; but the leaves are very curiously constructed. They have broad leaf-like petioles, at whose extremity there are two fleshy tubes, which form the real leaf, and which are armed with strong, sharp spines, three on the blade of each lobe, and a fringe of larger spines round the margin.
When an insect touches the base of the central spines the leaf collapses, and the poor insect is caught, been either impaled by the central spines or entrapped by the others. The leaf then remains closed, the fringe of long spines being firmly interlaced and locked together till the body of the insect has wasted away. This apparatus being the nearest approach to a stomach which has yet being observed in plants, an experiment was tried some years ago of feeding a dionaea (Venus's Fly-Trap) with very small particles of raw meat, when it was found that the leaves closed in the same way as they would have done over an insect, and did not open again until the meat was consumed. The leaves of this plant possess medicinal properties, which, when properly prepared in tincture or decoction, have been found of exceeding efficacy in many diseases of the digestive organs of the human being.
Sarracenia, or Side-Saddle flower, the leaves of which are pitcher-shaped, resembling an old-fashioned side-saddle, six of which generally belong to each plant. Each of these pitchers will hold nearly a wine-glassful, and are generally filled with water and aquatics, which undergo decomposition, or a sort of digestion, and serve as a nutriment to the plant.
This animal characteristic is also illustrated in the sensitive plant (Momosa Sensitiva), which the slightest touch suffices to make it close its folioles. If we cut with scissors the extreme end of one foliole the others immediately approach in succession. This irritation is not local, but communicates from circle to circle, and propagates itself from leaf to leaf. Up to a certain point it gets accustomed to outside interference. Touching it again and again will habituate it to the movement and fail to respond, as if it were owing in the first instance to fright.
The sleep of plants vaguely recalls to us the sleep of animals. Their period of sleep is mostly at night, and any interested person may observe this habit in a variety of plants, as many of them when asleep are difficult to recognize in their bearing. The leaves are rolled up, or become reversed, as in the genus Sida and the Lupinus. The Vetch, the Sweet-pea, the Broad Bean, in their sleep rest their leaves during the night one against the other.
Parental solicitude is displayed in the orach-root (Atriplex hortensis). The leaves of this plant fall back upon the young shoots, and enclose them whenever the effects of the atmosphere would injure them. This is also seen in the chickweed at night.
The folding of some flowers in the absence of the sun, and the opening of others as soon as that luminary has withdrawn his beams, are ascribable to various causes. The white marigold closes its flowers on the approach of rain, and the dwarf Colendrina folds up its bright crimson corolla about four o'clock every afternoon; while, on the contrary, the plant commonly called Four o'clock, whose flower remains closed all day, opens precisely at the hour of four. The evening primrose will not open its large yellow flower till the sun has sunk below the horizon. On the other hand, the Sun-flower is always seen bending its face (vis-a-vis) in the direction of the sun, and follows its course during the entire diurnal round, from its rise in the Orient, or East, in the morning, to its decline in the Hesperian region, or west, in the evening. The Silphium laciniatum, or compass-weed, always points its leaves towards the north star. The Night-blowing Cereus only expands its flowers about midnight. Indeed, some flowers are so regular in their opening or shutting, that the great botanist, LINNAEUS, formed what he called "Flora's Timepiece," in which each hour was represented by the flower which opened or closed at that particular time. An arrangement of this kind may be seen in the following Floral clock.