this genus is more or less prolonged, is in hyrax short, and is furnished with labial whiskers like many of the Rodentia. The habits of the animal much resemble those of the rabbit; it is very timid, and alive to the approach of danger. If this is, as is believed, the coney of Scripture, its description there is especially fitting. They are a "feeble folk," who "make their houses in the rocks," which are thus a "refuge for the conies." Though they can bite sharply when handled, they are in no way fitted for self-defence, and have a lively instinct of self-preservation, and are "exceeding wise" in availing themselves of shelter. They are gregarious, and, as I learn from a friend who has visited their haunts in the neighbourhood of the Dead Sea, they seldom leave the wild rocks among which they hide in the broad daylight, but for a short time about sunrise, and from an hour before sunset until dark. He has seen them, though never able to approach very near, coming out in parties to feed, and frolicking about in the nimblest fashion their heavy bodies and short legs allow, feeding on the young shoots chiefly of the Scilla maritima which abounds there, while one of their number is always posted on some ledge of rock to keep a look-out and warn them of danger; he does this by a plaintive warning cry, when they all immediately scuttle away to their holes-the slightest movement or shadow of the enemy is sufficient. They principally depend on the power of their sight, not on their hearing, which, from the form and the small aperture of their ears, is far less perfect than their sight; in fact, he has spoken to an attendant when on the cliffs immediately over head without disturbing them. Bruce, probably in ignorance of the nature of their food, tells how he shut up a tame one, fasting, with fowls and smaller birds, but "he never showed any alteration of behaviour in their presence, but treated them with a kind of absolute indifference." They are very cleanly, and are said to be good eating, but of this last we have no evidence. Note.-I have spoken of the hyrax as the coney of Scripture. Kitto says that it was first on the authority of the Rabbinical writers that the shâphân has been identified with the coney. There is no native rabbit in Syria; the only other animal which could be considered the shâphân was the jerboa, and this was held by Burckhardt; but the habits of the jerboa do not correspond with the Scriptural descriptions.-See Smith's Dictionary of the Bible, under the head of "CONEY." MOSSES have a species of arithmetical progression which, as far as we are aware, is peculiar to themselves; and on examining with the microscope the orifice of the little urn containing the spores or seed, we shall find that some genera, as Sphagnum (Bog Moss), Gymnostomum, Anæectangium, and Stylostegium (Beardless Mosses), etc., are destitute of the little circle of fringe which we call peristome, or teeth. Next in arithmetical order will come Tetraphis and Tetradontium, each possessing four teeth; then the lesser Yoke Moss, and Mr. Forster's Yoke Moss with eight teeth; then many genera with a peristome of sixteen teeth, others with thirty-two teeth, and others again with sixty-four. But we shall search in vain for any intervening numbers. The Tetraphis pellucida, fruiting in this month, has been selected for our present consideration. Its generic name is Explanation of the Cut.-Fig. 1. Tetraphis pellucida, nat. size. Fig. 2. Stem, showing crown of broadly ob-cordate leaves surrounding the gemmæ of the immature plant. Fig. 3. Capsule, mag. Fig. 4. Calyptra, mag. Fig. 5. Lid, mag. Fig. 6 and 7. Lower and upper leaves of the stem, mag. Fig. 8. Areolæ, or net-work of the leaf, highly magnified. derived from τετρα, for τετορα, four ; and a derivative of φυω, meaning a process or production, in allusion to its four prominences or teeth. It is a perennial, and grows in dense patches on the decaying roots of trees in shady and rocky places, as also on banks in a peaty soil. Having terminal fruit it belongs to the Acrocarpous section of mosses; and in the Calyptra, which is mitriform, irregularly plicate, and lacerated at the base, it has considerable resemblance to the Orthotrichums, which we considered in our July number; it also resembles them in the internal structure of the fruit, that portion of the columella which is included within the peristome, separating from the cellular tissue that fills up the interior of the lid above the peristome; a structure, it may be remembered, observable in Polytrichum.* The stems of Tetraphis pellucida are slender, erect, simple, or dichotomous, i. e., forked with the branches in pairs; when old crowded together, growing from a common base to the height of from half an inch to an inch, bearing small scattered leaves in the lower parts, but crowned with a tuft of larger, longer, and more crowded leaves at the summit, or with a cupshaped cluster of very broad leaves, surrounding a group of pedicellate lentiformet gemmæt. These leaves, except at the summit of the fertile stem, are mostly three ranked, ovatelanceolate, sub-erect, the upper ones larger and more spreading, variously curved, and entire in the margin; and under the microscope, they present a beautiful piece of hexagonal reticulation, from the shape of the areola, or spaces between the cellules of the leaf. The nerve ceases below the apex. The inflorescence is monoicous, the flowers are gemmiform or bud-like, and the barren flower issues from a branch growing out of an abortive fertile flower. The antheridia, which are analogous to the anthers of flowering plants, are mixed with filiform paraphyses, or succulent jointed, hair-like bodies, and the archegonia, which answer to the pistils of flowering plants, are few. The capsule is of a yellowish brown colour, sub-cylindrical, regular or slightly bent, with a red tumid border at the mouth, and seated on a reddish fruit-stalk about half an inch or more in length. The peristome is inserted below the orifice of the capsule, and permanently united to the included portion of the columella, which, with it, is divided into four pyramidal teeth, each being marked with longitudinal striæ. The calyptra is whitish, but brown at the apex; and the capsules usually solitary, though sometimes two are found together. The plant is of a light green above, reddish below, and at the base, con * Vide No. 16 of the INTELLECTUAL OBSERVER. Loose granular bodies capable of becoming plants. nected by closely interwoven and matted radicles, in colour approaching to a cinnamon brown. We give an illustration of the natural size of this moss, and also of its various parts magnified. It fruits throughout August and September. MARCET ON NOCTURNAL RADIATION. PROFESSOR MARCET communicated to the Société de Physique et d'Histoire Naturel the following paper on "The Effects of Nocturnal Radiation in Tropical Regions.' We translate it from the Archives des Sciences : "I profited," says the professor, "by the prolonged sojourn of one of my sons in Australia, to engage him in certain observations on the effects of nocturnal radiation in a climate so different from our own. With this end in view, I supplied him with the necessary directions, and with thermometers on whose accuracy I could rely. "Observations made during several years back at Geneva and Montpellier leave no doubt that in temperate climates, at the moment of sunset, provided the sky be clear, the temperature of the air in immediate contact with the soil is notably lower than the temperature of the same air at an elevation of a few feet. Although, so far as I am aware, observations had not been made in the region of the torrid zone, it appeared natural to conclude, à priori, that they would exhibit the same phenomena, with perhaps greater intensity, on account of the great transparency of the air, which is favourable to radiation; and because in those countries the surface of the earth is more strongly heated during the day, and might be expected to radiate with corresponding vigour during the night. I learnt, not without surprise, that this was not the case. It appeared, in fact, to result from a series of observations made by my son at his station on Logan Downs, in Queensland, 22° south latitude, and thirty or forty leagues distant from the sea, that the phenomenon of increase of temperature, in proportion to elevation above the soil, was not observed either at sunrise or sunset, or if it exists at all it is to an extent scarcely perceptible. He found, for example, by a series of observations made in March and April, 1862, under circumstances that were apparently very favourable to nocturnal radiation, that the difference between a thermometer placed at three centimeters above the ground, and another at a meter and a half above it, did not usually exceed from 0°,1 to 0°,2 Cent., three times it was from 0 to 3, and once from 0 to 4. "This result, completely unexpected by me, could not be attributed to an absence of nocturnal radiation from the soil, for this radiation, which depends on the heat acquired by the earth during the day, should evidently be more intense, other things being equal, in torrid than in temperate regions. We must, therefore, as it appears to me, seek for the explanation in the two following circumstances:-First. In tropical regions the heat of the sun is so intense that his rays warm not only the surface of the earth, but penetrate the soil to a certain depth. It follows from this that at sunset, when the surface of the earth begins to cool by radiation, the diurnal heat concentrated in the interior arrives at this surface, warms it again, and prevents the refrigeration of the stratum of air in immediate contact with it. The second circumstance which, according to my opinion, may explain the absence in certain tropical regions of the effects produced in temperate climates by nocturnal radiation, depends on the great quantity of water which the atmosphere holds in the form of elastic vapour, in a country whose mean temperature is elevated, as Queensland. The recent researches of Professor Tyndale have shown to what extent the elastic vapour of water operates to intercept the obscure heat emitted by the soil. This physicist has calculated that even in England, where the air must contain infinitely less vapour than in the torrid zone, it nevertheless suffices to intercept, at a distance of less than ten feet from the surface, the tenth part of the heat emitted by the soil. In tropical countries, and especially in those which are not far removed from the sea, the quantity of aqueous vapour contained in the atmosphere is no doubt more considerable, and the quantity of intercepted heat should be proportionately greater, and in consequence the effects produced by the nocturnal radiation of the soil less noticeable. "I have the more confidence in my son's observations as M. Lucien de la Rive has arrived at analogous results on the plains of Egypt in the neighbourhood of the Nile. M. de la Rive did not, it is true, attach to his observations the importance they probably deserve, partly because they were not very numerous, and partly because during the season at which they were made a decided wind frequently arose at sunset, and mingled the strata of the air so as to modify to a certain extent the phenomenon of temperature resulting from external radiation. I confess, however, that the analogy between his results and those obtained by my son in a country still nearer the equator, leads me to think, in the absence of more ample information, that the phenomenon of nocturnal radiation, and the effects which it produces, exhibit themselves in climates of the torrid region in a very different manner from that in which they are displayed in the temperate zone. |