Organdie

“ In the common sea-anemones there are, for instance, no organs of special sense, and no definite central nervous system. There are, however, scattered throughout the skin, and also throughout the lining of the digestive tract, a number of specially modified epithelial cells, which are no doubt delicate organs of sense. They are provided at their free extremity with a long hair, and are prolonged on their inner side into a fine process which penetrates the deeper part of the epithelial layer of the skin or digestive wall. ”

“ First, other congeries of glands occupy but a particular part of the system, or constitute a particular organ, as the liver, or kidneys; but those glands, which secrete the mucus, and perspirable matter, which are called capillaries, are of very great extent; they receive the blood from the arteries, separate from it the mucus, which lines every cell, and covers every cavity of body; and the perspirable matter, which softens and lubricates the whole surface of the skin, and the more extensive surface of the air-vessels, which compose the lungs. ”

“ Further, all epithelial cells, either of the outer or inner surfaces, whether forming special sense-organs and glands, such as the digestive and sweat-glands, or not, are connected with the nervous system. Besides these structures, there is another set of organs as to which we cannot speak definitely at present, which must be considered separately, viz. all the cells, together with their derived organs, which line the body-spaces. Whatever may be the ultimate decision as to this group of cells, it must fall into one or other of the two main groups. ”

“ We have, in the skeleton, a complicated apparatus of parts hinged and movable upon one another; the agent moving these parts is the same agent that we find in the heart walls propelling the blood through the circulation, in the alimentary canal squeezing the food along its course, and universally in the body where motion occurs, except in the case of the creeping phagocytes, and the ciliary waving of ciliated epithelium. This agent is muscle. We have, in muscular tissue, a very wide departure from the structure of the primordial cell ”

“ If this position be true we are warranted and justified in the conclusion that the germs necessary to form blood vessels and other parts of the body must look to the liver for the fluids in which they would expect to construct in form and size. It seems to be nature's chemical laboratory, in which are prepared by receiving chemical qualities and quantities to suit the formation of hard and soft substances, which are to become the parts and the whole of any organ, gland, muscle, nerve, cell, veins and arteries. ”

“ These units constitute the so-called muscular tissue. Of another tissue—viz., the nervous—the marked features are irritability and automatism, with an almost complete absence of contractility and a great restriction of the other qualities. In a third group of units, the activity of the protoplasm is largely confined to the chemical changes of secretion, contractility and automatism (as manifested by movement) being either absent or existing to a very slight degree. Such a secreting tissue, consisting of epithelium-cells, forms the basis of the mucous membrane of the alimentary canal. ”

“ The globule of albuminoid matter has developed into distinct members—sense-apparatus, organs respiratory, digestive, circulatory, locomotive, etc.—each of which has a separate task to fulfill, and is distinctly organized for that very purpose. It is no departure from our subject to remark that, though in the organic body one organ may, under certain circumstances, undertake the duties of another, such vicarious action involves grave peril to the organ concerned, and to the entire animal. ”

“ For example, in the case of the spleen, the capsule, trabeculæ, pulp, stroma, follicles and vessels should be examined; in the liver, the capsule, trabeculæ, liver-acini, blood-vessels and bile-ducts; in the kidneys, capsules, cortical surface, cortex, labyrinths and medullary rays, glomeruli, columns of Bertini, medullary pyramids, vessels, pelvis and beginning of ureter. When the organs are thus systematically examined there is but little chance that anything visible to the naked eye has been overlooked. ”

“ In simple epithelium, where there is only a single layer of cells, the cells may be pavement or hexagonal, columnar, glandular, or ciliated, according to their different functions. The flat pavement cells occur where a very smooth surface is required, as in the heart, lungs, blood-vessels, serous cavities, etc. None of these surfaces communicate directly with the external surface of the body and the name endothelium is substituted for epithelium. The columnar form of cell in the intestine facilitates the passage of leucocytes between the cells. ”

“ But there remain, broadly speaking, two other sets of organs whose size demonstrates their importance in the economy of the organism, yet whose functions are not accounted for in this synopsis. These are those glandlike organs, such as the spleen, which have no ducts and produce no visible secretions, and the nervous mechanism, whose central organs are the brain and spinal cord. What offices do these sets of organs perform in the great labor-specializing aggregation of cells which we call a living organism? ”

“ From the outer layer, or epiblast, are developed the permanent epidermis and its out-growths, the nervous system, and the organs of sense. From the introverted layer, or hypoblast, are developed the alimentary canal and those parts of its appended organs, liver, pancreas, &c., which are concerned in delivering their secretions into the alimentary canal, as well as the linings of those ramifying tubes in the lungs which convey air to the places where gaseous exchange is effected. ”

“ The cells must function quickly to prevent disharmonious substances from entering the circulation. To ensure the proper discharge of a duty so important to the organism, the liver is placed between the intestines and other organs. Within this important organ the blood, still laden with the absorbed and partly metamorphosed food-stuffs, comes into contact with the liver cells. This material is once more thoroughly sifted, and the blood is finally discharged into the general circulation, freed from all substances that would be out of harmony with the body and the blood. ”

“ The serous surfaces are capable of being influenced by the affections of the other organs; this is very evident in the organic diseases of the heart, the lungs, the liver, the spleen, the stomach, the womb, &c. organs, which without having any known connexion of functions with the serous surfaces, influence them however so that all their morbid defects of organization are accompanied, in the latter periods, by different serous collections in the great cavities, collections evidently owing to a derangement of the organs which constantly exhale this fluid. ”

“ There is, as we shall see more clearly, a structure, the respiratory atrium, not apparently represented in the true vertebrate types, at least in their adult stages. There is no distinct heart, only a debateable brain, quite without the typical division into three primary vesicles, no skull, no structures whatever of cartilage or bone, no genital ducts, no kidneys at all resembling those of the vertebrata, no pancreas, no spleen ”

“ No one who has eaten a cutlet, a sweet-bread, a kidney, a piece of liver, heart, tongue, and tripe, need be reminded how various are the different organs in composition. All this variety, however, the body brings about itself, marvellously [pg 345] selecting from the one raw material, blood, the different substances and the appropriate quantities for each kind of tissue.
Out of the blood the body takes the compounds containing calcium, phosphorus, oxygen, hydrogen, carbon, and some other things, for the making of the skeleton. ”

“ Numerous experiments have shown, as has already been mentioned, that definite cells depend upon definite secretions having their origin in other organs. If we remove certain organs, for instance the thyroid gland, the accessory thyroids, the sexual glands, the suprarenal bodies, and so on, we get definite degenerative phenomena appearing. In many instances, indeed, the absence of these organs is incompatible with life itself. The same phenomenon manifests itself when the organ is left in its proper place, but through some cause or other gradually discontinues its proper functions. ”

“ They exhibit a division of labour: some carrying on the work of digestion; some, which we call nerve-cells, receiving and conducting stimuli; some, which we call muscle-cells, altering their form—in fact, contracting in one direction—under the action of the stimuli brought to them by the nerve-cells. In most cases a number of cells with the same function are united together, and thus constitute a tissue. Thus the cells which carry on the work of digestion form a lining membrane to a tube or sack, and constitute a tissue known as a secretory epithelium. ”

“ Not only is the rigidity and firm consistency of the muscles altogether wanting, but these structures have lost that deep reddish color which normally exists. When the abdominal cavity is opened a more or less abundant, clear, limpid, or yellowish fluid will make its escape, and the entire visceral contents will, at the same time, display a remarkably blanched aspect. These pathological changes are also shared by the important organ especially affected, namely, the liver. ”

“ The matrix of botryoidal tissue is a network of stretched and hollowed connective tissue cells-- it is not a secretion, as cartilage matrix appears to be. During digestion, the phagocytes prowl into the intestine, and ingest and devour bacteria, that might otherwise give rise to disease. ”

“ In fact, when the organs begin to be developed in this mass, the spaces that are left between them are filled with a substance which, exactly similar to that which before formed the whole of the body, can be considered as the residue of it, or rather perhaps it exists in a distinct manner, because it has not been penetrated with the peculiar nutritive substance, like that which forms the parenchyma of nutrition of the organs, which before this penetration resembled it precisely. ”

“ Each organ has as yet only its nutritive parenchyma, the parenchyma upon which nature has imprinted the form of the organ, that is to be developed there. In proportion as this outline is increased, the nutritive substances penetrate it, and then each organ, which until that time had been like the rest in its nature, and forming with them a homogeneous mass, begins to be distinct, and have a separate existence; each one draws from the blood the substance that is proper for it. This addition gives the attributes of thickness, of density, and of nature ”

“ Valuable service is rendered to research as a whole, if every case, which gives an unexpected result in respect of its reaction, is thoroughly investigated. In the first place the dialysation tubes should be changed, or else another organ should be used. If the result always recurs, we still have to exclude the possibility that, in the organ used, substances are inherent which are also contained in other organs. In saying this we are thinking of such a case as the following. It may be that an individual has some diseased connective tissue in some part of his body. ”

“ Each organ has the shape of a biconvex lens, sunk to about half its thickness in the skin. The inner half is formed of radially-arranged gland tubes filled with small granular cells, and converging towards the centre of the organ. Into the connective-tissue walls of the tubes extend blood-vessels and nerves. External to the gland tubes there is a layer of long slender cells arranged perpendicularly to the surface, and more externally still a layer of ganglion cells. There is evidence that these organs multiply by division. ”

“ The cells, the special anatomical elements of the liver, the kidney, and the brain are reduced by atrophy and degeneration. At the same time, the conjunctive woof which serves them as a support develops, on the contrary, at the expense in a measure of the higher elements. For this reason the tissues harden. We know that the flesh of old animals is tough. We know in pathology that this is happening to the tissues. It is due to growth, to injury to the active and important elements, to the elements of support of the organs. ”

“ Let us not, however, exaggerate this independence of the textures of the organs in diseases, lest experience should contradict us. We shall see that the cellular system is oftentimes a medium of communication, not only from one texture to another in the same organ, but from one organ to a neighbouring one. ”

“ As the body is composed of individual organs, and each organ of separate tissues, so each tissue is made up of minute cells. Each cell is a little world by itself, too small to be seen by the naked eye, but open to the microscope. It has its own form and constitution as much as a special organ in the body. It absorbs from the blood such food as suits its purposes. Moreover, the number of cells in an organ is as constant as the number of organs. As the organs expand with the growth of the body, so the cells of each tissue enlarge, but shrink again with age and the decline of life. ”

“ I say in the first place, that the parenchyma of nutrition is the same for all the organs, and that it is an assemblage of red vessels, of exhalants, of absorbents, of cellular texture, and of nerves; these are the proofs. 1st. These different organs are met with in all the others, as I have observed before, anatomy shows them every where, between each fibre, each layer, each point, if I may so say; they are truly the common organs. ”