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of the utricles and the captures contained in them. Specimens of new growth, showing the just forming utricles and the peculiar circinate mode of growth, should be included on the slide. The mounting should be in carbolated water.

The Pinguicula, another of the insectivorous plants, is found abundantly on the more open plains, and not far from wet places. It is a compact rosette of very light green leaves, growing close to the ground, from the centre of which rises a single flower stalk eight or ten inches high. The leaves have their edges turned up forming a shallow trough, and on the upper surface are mushroom glands which exude a viscid secretion. Insects are caught and held by this sticky substance until they die. The nutritious matter is then dissolved out by an acid secretion, and this is ultimately absorbed into the substance of the plant by the glands on the leaf. The edge of a leaf when excited by a capture will bend over upon it for a short time,—merely for the purpose, I think, of more effectually securing it, and of bathing it in the secretions.

The calyx and flower stalk, as I have already mentioned, are thickly covered with the same mushroom glands that are found more sparingly on the leaves. I have never seen any evidence that t flower appendages took any part in the digestion of insects. They seem to be rather in the nature of an ornamentation, than of anything useful. For exhibition, therefore, or for double staining, the calyx and flower stem will be found by far the most attractive part of the plant. The best way to preserve them, as well as all such small material, until wanted for use, is to put them green into a common morphia vial with a few drops each of alcohol and water, and then to cork and seal them up tight with melted beeswax. To prepare them for the slide, these objects may be treated precisely as recommended for sections of castor-oil plant, but should be mounted in a weak solution of glycerine in camphorated water.

If cells are made of rings punched out of the thin sheets of colored wax used by artificial flower makers, and then coated with either liquid marine glue, or a mixture in equal parts of gold size and gum damar dissolved in benzole, this method of liquid mounting may be as easily and safely performed as mounting in balsam. In very many cases simple water, made antiseptic in any manner, will be found far preferable to any other media, both for retaining the full and distended forms of minute organs, and for bringing

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out the delicate markings of vegetable structure which the highly refractive balsam would entirely obliterate.

There is only one other insectivorous plant found in Florida — the pitcher plant, Sarracenia variolaris, a species growing only in the South Atlantic States. It is found in low and wet places among the open pine barrens, but is not as abundant as the others which have been mentioned. The leaf is a hollow, conical, or trumpet-shaped tube, with a flange or wing running up one side, and a hood which arches over the orifice of the tube. During the growing season this tube is usually more than half filled with water, which we must suppose secreted by the plant itself, because the hood effectually sheds all rain water from it. Crowded into the bottom of the tubes of mature leaves we shall almost invariably find a mass of the hard and indigestible parts of insects. These creatures have been in some way attracted into that suspicious looking receptacle, and once in have been unable to get out again. A mere partially covered tube, however, with a little water in it, is by no means a fly-trap. Not one insect in a hundred would fall into that well and drown, if there were not some special device absolutely preventing it from crawling upward. Now a microscopical examination of the inside of the hood and tube of the pitcher plant reveals the most skilful contrivances for securing insect prey that could possibly be imagined. In the first place, there are in the upper part of the receptacle, and about the mouth, great numbers of sessile glands which secrete abundantly a sweet fluid very attractive to ants and flies. Further, there is, on the inner surface of the hood and mouth, a formidable array of comparatively long, pike-pointed spines, all pointing backward and downward. These grade off into shorter, more blunt, but still exceedingly sharp-pointed spines which overlap each other like tiles on the roof of a house. This kind of coating lines the tube for a third of the way down, the spines growing finer until at last they grade off into regular hairs which line all the lower part of the tube; spines and hairs all pointing downward. An insect, attempting to retrace its steps after its ambrosia. feast, would find nothing which it could penetrate or grasp with the hooklets of its feet; and the wetness of the spines, from the constantly overflowing glands, would probably prevent it from making use of any other device that insects may have for climbing glazed surfaces.

As a matter of fact, no creature comes out of that prison house; unless it be with the single exception of one cunning spider, which in some way finds a safe and rich retreat under the hood of its great vegetable rival.

The bodies of the captured prey fall into the fluid in the tube, and are macerated or decomposed, but without any signs of puTherefore the plant must at once absorb the animal matter, for otherwise this would cause the infusorial life which is called putrefaction.

trescence.

In order to show the internal structure of the pitcher plant leaf, it will be necessary to separate the cuticle which bears the spines and glands from the rest of the leaf. To do this pieces cut from the leaf, and preferably those showing the transition from one kind of spines into another, after being soaked in water, may be put into common nitric acid, and this brought up to the boiling point over an alcohol lamp. They should then be immediately washed in several waters, when it will probably be found that the cuticle, both the inner and the outer, has already separated from the parenchyma. The specimens will need no further bleaching, and may be stained either in eosine, the aniline orange color, dissolved in water, or in aniline blue in alcohol. As there is only one kind of tissue to be stained, it will be impossible to get more than one color in them. They should be mounted, or kept in water very slightly acidulated with carbolic acid.

I cannot but regard the pitcher plant as the most highly developed, the most specialized in its organization of any of the insectivorous plants. It differs more widely from ordinary vegetation, and has more special and adapted contrivances about it than any of the others. Now, as I believe that the truth of the modern evolutionary theory will be eventually brought to the test by well studied monographs, made by microscopists, on some such highly differentiated organic structures as the pitcher plant, I do not deem it a digression to present here briefly some inferences which seem to me to arise from the developmental history of this particular plant.

Of course, if the pitcher plant was developed from other and ordinary plants, it had at one time the simple plain leaves of common herbs. It must have early commenced, in some way, to appropriate insect food on these leaves, because every essential change was for the betterment of the plant in this respect. The

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stem of the leaves soon began to put out flanges or wings on each side the phyllodia of the botanists, which are not uncommon among plants. And these outspread wings must have assisted in the absorption of insect food that was washed down upon them. Then the edges of the wings turned up, and curved around towards each other, until finally they met and grew together, forming a tube and a much more complete receptacle for decomposing animal bodies. A South American genus, the Heliamphora, is just in this condition at the present time. Then from some unknown cause, and in a way exceedingly difficult to explain, our Sarracenia changed entirely its manner of capturing insects. The leaf bent over the orifice of the tube, forming the hood, and those remarkable spines and tiled plates were developed on the inside of the hood and tube, growing backwards contrary to the order of nature. When all this was accomplished and fully completed, but not before, our plant could commence its career as the most successful trappist of either the vegetable or the animal kingdom.

Now, according to the Darwinian theory, all these transformations were the result of innumerable slight and accidental variations, each one of which happened to be so beneficial to the particular plant concerned, that it got the start of all the others and every time run them all out of existence. One cannot tell how many million times this extinction and reproduction must have occurred before our marvellously perfect little flytrap was finally produced. Excuse me, if I confess that all the canonical books of Darwin are not sufficient to make me put faith in the miracles of accidental evolution. I believe in the fact of the gradual development of the organic kingdoms; for all science teaches it. But I believe it was governed and guided by forces more potent than accident and chance. The Being, or the first cause, if you will, that originated the simple elements of matter, and endowed them with the power and the tendency to aggregate into developing worlds, might equally as well have endowed certain of them with the power and the tendency to aggregate into ever-advancing organisms. There is no chance in the myriad forms of crystalline and chemical substances; then why should there be in the scarcely more varied colloid forms of living matter? In a world that unfolds from chaos in one steady line of progress, that shows only design at every advancing stage, I must logically place somewhere at its commencement the Almighty fiat of a Designer.

SULPHURIC-ACID TREATMENT OF SEEDS AND ITS VALUE TO COTTON PLANTING AND CULTURE. BY THOMAS TAYLOR, of Washington, D. C.

WHILE making some microscopical examinations about fifteen months ago, to determine the position of the oil-cells in Indian corn, I found that the germ of this seed was remarkably well protected from accidental injury. It is surrounded by a series of oilcells, outside of which are many layers of starch-cells, filled with granules of starch. Bounding these cells is a second series of oil-cells in close contact with, and under the external cellulose coating of the seed.

As one of the results of this investigation, it occurred to me that seeds of this structure might with entire safety be subjected to chemical action, with a view to effect certain chemical changes, in those outer portions which serve as nourishment to the germ, thus accelerating the process of germination. For the purpose of experiment on this point, I selected sulphuric-acid for the reason, that, like diastase, this agent has the property of converting starch and dextrine into grape sugar, substances used as plant food in the germination of the embryo.

Indian corn is a type, in its internal structure, of a large class of seeds. The, cotton-seed is a conspicuous example of another class.

In the cotton-seed the entire space inside the pericarp is occupied by the embryo or miniature plantlet. This plantlet, it removed and subjected to chemical treatment, will be seen, by the aid of the microscope, to be charged with starch, oil and albumer, thus showing that the plantlet contains within itself the food necessary for its proper germination.

Owing to such differences of structure, the action of sulphuricacid is not alike on all seeds. In one case the acid may be employed to act directly on the proximate principles of the seed, while in others, as in the case of the cotton-seed, its action may be confined to the process of reducing the non-conducting substance of the hull, so that heat and moisture from without may have more ready access to the germ or plantlet.

In the cotton-seed, the benefits of the acid treatment are conspicuously manifest. The cotton-seed of commerce is covered with matted short fibres of cotton, firmly adhering to the compact woody shell or pericarp. As a result of experiment, I have found

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