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NEW FACTS IN ECONOMIC BOTANY:

THE PROPERTIES OF THE GENUS CORIARIA.—THE LEAVES OF THE

DAGGER PLANT.

BY JOHN R. JACKSON, A.L.S.,

Curator of the Museum, Kew.

The genus Coriaria has long been one of interest to botanists, owing to peculiarities of structure, from which it has been placed by various authorities in different natural orders, and by some the characters have been considered sufficiently distinct to constitute a separate natural order under the name of Coriariæ, which arrangement has been confirmed by Dr. Hooker and Mr. Bentham in their Genera Plantarum, where the order is placed between Anacardiaceæ and Moringeæ. Four or five species of Coriaria are known. They are found in southern Europe, Peru, New Grenada, New Zealand, Nepal, etc. They are all shrubs, with opposite, simple, ribbed, entire, ovate, cordate, or lanceolate leaves. The flowers are white, and hang in clusters, and are either monæcious, diæcious, or hermaphrodite. The calyx is five-parted and bell-shaped, and the corolla has five fleshy petals, from the base of which, and beneath the ovary, spring ten stamens. The fruit is composed of five carpels, seated upon a thickened receptacle, and surmounted by five stigmas.

In New Zealand, Coriaria sarmentosa is called the “Tutu," or wine-berry shrub, from its shining, black, berry-like fruits, being full of a sweet, dark-red juice, which the natives express both for use as a beverage and also for soaking their baked fern-root in before eating. It is remarkable that the seeds themselves are highly poisonous, but the juice, when expressed and strained, is quite harmless. This, however, has some analogy in the fruit of the Strychnos nux vomica, the seed in that fruit being, as everyone is aware, the seat of the alkaloid strychnine, while the pulp which surrounds the seed is eaten and relished by the natives in many countries where the plant grows. The effects produced by eating the seeds of C. sarmentosa, Forst., are convulsions and delirium, which in many cases continue several hours, and frequently terminate fatally.

A case is recorded in a New Zealand paper of a man belonging to one of the native regiments having nearly killed himself by eating these berries. The symptons, it is said, strongly resembled

those of poisoning by strychnine. · Chloroform was administered, the inhalation of which quickly relieved the patient. When chloroform is not at hand, an injection of half a drachm of extract of conium, mixed with a pint and half of warm water, and given occasionally as the fits of delirium come on, is said to be the next best remedy. Camphor, oil, or soap, are also recommended as good antidotes.

The most remarkable instance of the poisonous properties of the Coriaria is mentioned in a letter from Dr. Haast, of Canterbury, New Zealand. It occurred to an elephant which, after being landed at Otago, was marched inland by its owner for a considerable distance. Arriving at a suitable halting place, where the vegetation was abundant, the owner determined to give the animal a spell of a few days' feeding. The grass, which had been burnt off during the previous season, had shot up again with renewed vigour, and amongst it was a very fine crop of succulent young plants of Coriaria. The elephant fed amongst this herbage for four hours, and afterwards went to a neighbouring creek and had a long drink. In turning back, the animal began to reel, fell on the ground, and died after three hours ; so that it took only seven hours from the time the beast began to feed amongst the plants until he died. It would seem from this instance that the poison must be very virulent. It is, moreover, remarkable that the elephant should, like sheep and cattle, eat the plant, while the horse will not touch it.

A similar poisonous property seems to reside in C. myrtifolia, L., a deciduous shrub, with myrtle-like foliage, native of Europe, the fruits of which are reported to have caused the death of several French soldiers in Catalonia. The leaves, which likewise contain some proportion of the same poisonous principle, have been used to adulterate senna, and serious consequences have been the result. The poisonous principle from this species has been extracted in France, and called by chemists Coriamyrtine.

A species of Coriaria, C. thymifolia, H. B., grows in Peru and New Grenada, and is there called the Ink Plant, from the fact of the juice being used as a substitute for ink. There is indeed a tradition prevalent in New Grenada, which is worth recording here. It happened during the Spanish administration that a number of written documents, destined to the mother country, were embarked in a vessel and transmitted round the Cape. The voyage was unusually tempestuous, and the documents got wetted with salt water. Those written with common ink became nearly illegible,

whereas those written with “chanchi” (the name of the juice) remained unaltered. A decree was therefore issued that all government communications should in future be written with the vegetable juice. Whether this story is true or not, we are not in a position to vouch; but Dr. Jameson, the Professor of Botany at Quito, writing to a friend in England, says that he generally uses this vegetable ink in preference to the commercial article, as it does not so readily corrode a steel pen. The ink, when first used, has a reddish tinge, but becomes quite black after a few hours.

These plants, then, it will be seen have, besides a botanical, a peculiar economic and chemical interest, which we think are worth investigation by those who reside in the localities where they grow, and who thus have facilities offered them for such an examination.

A new material for ladies' bonnets, together with a bonnet made of the same, has recently been received at the Kew Museum. The material in question is the prepared epidermis of the leaves of the West Indian Dagger Plant, Yucca aloifolia, L. This grows to a large size in the West Indian islands, and consequently produces leaves of greater length and width than those yuccas usually seen in our own gardens; so that a tolerable length of material is yielded by one leaf.

The preparation and application of this new material is due to the ingenuity of a Mrs. Josephs, of Falmouth, Jamaica. Her mode of proceeding, however, has not transpired. The substance is simply the epidermis of the leaf, thoroughly cleansed of all succulent and fibrous matter, and then apparently carefully bleached, perhaps with chloride of lime, or dyed, as occasion requires. In the Kew Museum are specimens simply bleached as well as dyed, the colours (mauve and blue) being derived from Judson's dyes, now so much advertised for ladies' use.

Though so delicate, and apparently fragile, this material is said to be very durable, not readily taking the dirt or changing colour. If it can be produced and prepared in Jamaica, and sent to this country at a sufficiently cheap rate to make it "pay,” we have no doubt it may

become an article of trade; that is, of course, providing a supply could be ensured to meet the demand : and, considering the small quantity of material required at the present time to make a bonnet, there seems to be no probability of a failure on this

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COCCOLITHS AND COCCOSPHERES: AND NOTES ON

ORGANIC BODIES IN REIGATE FIRESTONE.

BY HENRY J. SLACK, F.G.S., SEC. ROYAL MIC. SOC.

(With a Plate.)

The recent acquisition of knowledge concerning deep-sea life, has materially increased the interest attaching to the organic bodies known as Coccoliths and Coccospheres. These objects do not exhibit any preference for depth. Dr. Wallich informs me that they are readily obtained, for example, off the coast of Plymouth, at about seventeen fathoms; but they appear to play an important part in regions far below those in which any of the higher species of marine plants have been found. The sketches appended hereto will show those who are unacquainted with them the general appearance of these objects, better than a verbal description. (See Plate.)

They were first noticed by Ehrenberg in chalk, and described by him as mineral concretions of particles derived from organic bodies. Not having the original (paragraphs of the Prussian naturalist before me, I quote from the “Micrographic Dictionary" (article Chalk) "The cementing material of chalk consists of very minute, numerous, and remarkable bodies called crystalloids. They are elliptical, or rounded and flattened, from 1-10,000" to 1-2,500" in length; the most numerous, perhaps, 1-3,000"; some of them consist of a simple ring, in others it is marked with pretty regular transverse lines, so as to make it appear jointed; in others again there is a thinner central portion, often exhibiting one or more granules. M. Ehrenberg regards these as arising from the disintegration of the microscopic organism forming the chalk, into much more minute calcareous particles, and their reunion into regular elliptical plates (or disks), by a peculiar process, differing essentially from, and coarser than, that of crystallization, but comparable with it-one probably preceding all slow crystalline formations, and causing, but not alone, the granular state of solid inorganic matter." This very gratuitous hypothesis was not found conformable with subsequently discovered facts. The Rev. J. B. Reade first recognized the "crystalloids” as organic, Mr. Sorby noticed their resemblance to recent objects from the sea-bed, and they were investigated by Dr. Wallich, Professor Huxley, and others. Mr. Sorby figured chalk Coccoliths (as Professor Huxley called them) in the “ Annals of Natural History," 1861. He noticed a radiatory arrangement of the carbonate of lime, and sketched some of a granular character.

The easiest way to see these objects is to place a drop of water on a slide, and rub into it a particle of chalk in the shape of whiting, cover with glass, illuminate with one of the small stops of an achromatic condenser, and employ a power of about 500. Fig. 2 represents Coccoliths and other minute bodies drawn from a slide so prepared. It will be found that the Coccoliths are by no means uniform in size, exact appearance, or degree of convexity.

In the “Annals of Natural History” for the same year, Dr. Wallich mentioned the abundance of Coccoliths to be found in the sea-bed, and he described and figured “Coccospheres ” as “minute spherical cells, having a defined limitary wall, and upon their outer surface the Coccoliths of Professor Huxley, arranged at nearly regular intervals. The cells when crushed are seen to contain a homogenous, gelatinous, and almost colourless matter, exhibiting no visible trace of organization, and in all probability consisting of sarcode. This wall of the cell may be distinctly seen under a high power; but from the minuteness of the entire structure I am unable to do more than attest its existence." Dr. Wallich met with the cell in a fractured condition.

He further says, “Coccoliths are of an oblong shape, concave in their internal aspect, namely that on which they are attached to the surface of the Coccosphere cells, and convex externally. In short they are spoon-shaped, only with a much less marked concavity.He found their average length 1-2,700", and suggested that as they occurred in adhesion to Textularia, there might be some connection between the two.

Dr. Wallich's figures exhibit a tendency to a dotted or beaded formation, and in one sketch he showed two small central spots.

Professor Huxley read a paper on this subject before the British Association (reprinted this year in “Quart. Jour. Mic. Soc.," October, 1868). He referred to Captain Dayman's soundings in 1857, in the North Atlantic Telegraph Plateau. In the mud thus obtained he found the Coccoliths, and assumed them to be inorganic because they were rapidly dissolved by dilute acids. Thus they received their doubtfully appropriate name of Coccoliths, or “berry-stones."

Captain Dayman found the fresh mud from the Atlantic sea-bed very sticky, and Professor Huxley ascertained this to arise from the presence of a gelatinous substance in lumps of all sizes, from patches visible with the naked eye to excessively minute particles. They contained “granules, Coccoliths, and foreign bodies.” “Solution of iodine stains the granules yellow, while it does not affect the

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