Syce

“ Other observers maintain that the amoebae may pass through the walls of the intestine, through the peritoneal cavity, and so on to the liver where they give rise to typical abscesses.
Syphilis. — It has long been recognized that syphilis is a specific infective disease, but although characterized by fever, anaemia, and increased growths of tissue followed by rapid degeneration and ulceration of tissue, it is only within quite recent years that a definite parasitic organism, present in all cases of typical syphilis, has been isolated and studied. ”

“ A larger or smaller quantity of fluid is present, and also a connective-tissue sheath; the host is a vertebrate. Cysticercus (true bladder-worms) , Piestocystis, Cœnurus, Echinococcus.
II. The caudal bladder arises from the proscolex by budding, that is, by the formation of new parts; there is no connective-tissue sheath, and the host is an invertebrate. Cysticercoidei, Leuckart. (a) Caudal bladder formed by endogenous budding; the head is surrounded, not only by the body of the worm and the caudal bladder, but also by the blastogen (proscolex) . ”

“ The cysts or envelopes in which the parasites live are dissolved by the digestive fluids and the young larvae which are liberated develop in the small intestine to the adult worm, usually within two days. The young embryos, which are produced in great numbers by the mature worms, gain entrance to the lymph channels and blood stream, and after about ten days begin to invade the muscles—a procedure which gives rise to many of the most characteristic symptoms of the infection. ”

“ That principle is that if the cells of the scions are distended with water a certain chemical process is going on all the while, because a scion is just as much alive as the red squirrel; it is a living organism. ”

“ This kernel then dries as you see here, but when the nut falls on favourable soil, the germ within the kernel swells until it bursts through the shell, and, taking root, springs up a new tree.'
`I do not understand,' said Fritz, `how the little germ manages to get through this great thick shell, which is not like an almond or hazel-nut shell, that is divided down the middle already.'
`Nature provides for all things,' I answered, taking up the pieces. `Look here, do you see these three round holes near the stalk; it is through them that the germ obtains egress. ”

“ When that occurs, the cyst is dissolved and the minute fluke works its way down the alimentary canal into some part of which it inserts its suckers and commences to feed on the blood of its host. Occasionally the fluke migrates into the blood vessels and may reach the lungs, kidneys, urethra and bladder. In the course of a few months it attains full size and maturity and probably in most cases dies in the course of a year after having given rise to another generation of larvae. ”

“ This explains why we so commonly find cysticerci scattered in cysts along the intestines and between the membranes of the mesentery, and how they can, by piercing the walls of the vessels, spread themselves into the most distant organs, by means of the blood which conveys them. When the embryos have once pierced these walls, they hollow out the tissues in all directions, until they find themselves in the muscles, or in the organ which is indicated in their itinerary. When they have arrived at their destination, they stop and surround themselves with a sheath ”

“ In the pig the diagnostic sign of swellings of the glands or ‘cyst’ under the tongue is not found in ‘Cysticercus,’ and the disease called ‘measles’ is not ‘Cysticercus,’ but a mere superficial inflammation of the skin and a symptom of fever. ‘Cysticercus cellulosus,’ as its name shows, infects the cellular tissue only of the pig, and cannot be discovered in life by any abnormal condition of skin. ”

“ If the soil in the bench is wet, there is too much water; if it is dry, it is too dry, of course. If the ventilators are up, there is too much air; if the ventilators are down, there is not enough air. ”

“ Some of the bacteria have the power of motion generally produced by cilia or flagella and others are motionless.
Habitat. These organisms may truly be said to be omnipresent. Every thing we wear or use or eat, even the air itself, is impregnated with them. Pathogenic germs may also be found among these myriads. Every species has its own particular habitat, where the conditions especially favor its growth, just as any of the larger plants require a certain soil, a supply of water, temperature, and proper amount of light in order to make growth and multiplication possible. ”

“ Peculiarities of the Germ.—Many interesting facts about the Spirochæta pallida explain peculiarities in the disease of which it is the cause. Many germs can be grown artificially, some in the presence of air, others only when air is removed. The germ of syphilis belongs in the latter class. The germ that causes tuberculosis, a rod-like organism or bacillus, can stand drying without losing its power to produce the disease, and has a very appreciable ability to resist antiseptic agents. If the germ of syphilis were equally hard to kill, syphilis would be an almost universal disease. ”

“ The units of the colony live inside a common system of tubes, which they secrete; each unit, when adult, is independent, and can move about inside the tubes; the disc is used as a means of attachment to successive spots of the tube-wall, as the animal wanders from place to place. Above the disc are twelve plume-like tentacles covered with cilia, which create a current in the water surrounding the head, and wash food particles into the mouth. ”

“ Respiration.—The oxygen of the atmosphere dissolved in the sea-water is, in default of a special circulatory fluid, brought to the tissues of Polyclads in two ways. The ciliated epidermis provides a constant change of the surrounding water, by which the superficial organs may obtain their supply; and the peristaltic movements of the digestive system, aided by the cilia of the endoderm cells, ensure a rough circulation of the sea-water, which enters along with the food, to the internal organs. ”

“ The anus (cytopyge) is terminal. The macronucleus is usually horse-shoe or kidney-shaped, sometimes oval; the micronucleus contiguous. Reproduction is by binary fission and conjugation, and encystment occurs. The cysts are spherical or oval. These ciliates are parasitic in the large intestine of human beings and pigs, in Amphibia, and in the body cavity of polychæte Annelida.
Fig. 113.—Balantidium coli. a, nucleus; b, vacuole; c, peristome; d, bolus of food. (After Leuckart.) ”

“ Reaching the intestine and especially the cæcum and colon they bore their way into the mucosa and encyst themselves, or if they happen to perforate a blood-vessel they make a habitat of that. In the cyst, development proceeds and when it has reached a certain stage the worm once more bores its way through the mucosa and reaching the intestine becomes sexually mature. ”

“ If these cysts be repeated in the direction of the axis, the tegument becomes an annulated skin. An annulose animal is a multiplied cystic animal. Associated with this character, the respiratory organs are gradually evolved to form vascular plexuses, branchiæ, feet, tracheæ, and wings, while the sexual parts are for the most part separated—Ancyliozoa, Respiratory animals. ”

“ Every living cysticercus which penetrates into the stomach, instantly quits its torpid state: it gets rid of its useless parts, abandons its former cavity, penetrates into the intestine, attaches itself by its new hooks and its suckers to the enclosing membranes, and grows with such rapidity, that in less than six weeks, we often find a tape-worm many metres in length. ”

“ The remote cause of sitis frigida, or cold thirst, is owing to the inaction of the cutaneous, pulmonary, urinary, and cellular absorbents; whence the blood is deprived of the great supply of moisture, which it ought to receive from the atmosphere, and from the cells of the cellular membrane, and from other cysts; this cause of thirst exists in dropsies, and in the cold fits of intermittents. The desire of fluids, like that of solids, is liable to acquire periods, and may therefore readily become diseased by indulgence in liquids grateful to the palate. ”

“ TINEA SYCOSIS.—Tinea sycosis, or parasitic sycosis, is a disease confined to the hairy portions of the face and neck in the adult male, involving the hair and hair-follicles, with inflammation of the skin and subcutaneous connective tissue, and the formation of tubercles and pustules. It is popularly known under the name of barber's itch. It usually begins as one or more small, red, scaly spots, similar, in fact, to ringworm on the non-hairy portions of the surface. The redness and scaliness increase, and swelling and induration are noticed. ”

“ Every animal cyst is necessarily composed of the element of the vesicles, and is then for the first time an organ. The vegetable bladders are, however, single vesicles, and as such are already an organ. In the plant therefore the cellular tissue is upon the lowest stage, being only an aggregate devoid of secondary form; in the animal along with its aggregation a secondary form has been imparted. In this the higher character of the animal is at once demonstrated. ”

“ Frequently the individuals of a colony are grouped into systems, in which the atrial orifices open into a common cloaca. The little ascidiozooids vary greatly in shape in the different families. In the Polyclinidæ, for instance, they are long, the organs being so to speak, drawn out, and being arranged in three regions, the thoracic, abdominal and post-abdominal, the first region containing the branchial sac, the second the stomach, and the third the heart and reproductive organs. ”

“ Those which do injury to the host are called pathogenic or disease-producing, as the organisms causing the transmissible diseases of animals and plants.10 Finally, we have those parasites which are of benefit to and receive benefit from the host. These are called symbionts or symbiotic parasites and the mutual relationship symbiosis. Certain of the intestinal bacteria in man and especially in herbivorous animals are undoubted symbionts, as are also the “root-tubercle bacteria” already mentioned. ”

“ It is a very common object, and possesses a red eye-speck close to the “contractile vesicle.” All Infusoria have the latter, some a great number, as in Fig. 9. The vesicle contracts at regular intervals, and is then simply blotted out, but reforms in the same place, so that it is probably the heart or the urinary bladder of these minute animals.
The lovely rosette shown in Fig. 4 is the Synura, a spherical colony of zoöids, each of which has two flagella, and is in addition clothed with rows of cilia. A beautiful sight it is to watch these colonies rolling through the field of view. ”

“ Treatment.—In the treatment of bacillary dysentery absolute rest in bed is important to keep up the strength of the patient and also to protect the heart which tends to be more or less damaged by the toxic action of the Shiga bacillus. Some prefer to prop up the patient in bed, considering a strict dorsal decubitus as undesirable. It is important to use sufficient covering on the patient to avoid chilling. A light wool blanket spread over the abdomen is often all that is needed in the tropics. ”

“ In one small separate cell lay two syphilitic patients — a man and a woman together, as there was no ward for women suffering from that disease — and on a pile of rags under a table in one corner of that same cell lay, cowering and getting behind each other, like puppies or kittens, two little children under three years of age belonging to the woman. ”

“ The post-mortem examination revealed a healthy condition of the whole of the intestines, save slight thickening of some parts of the colon and rectum, which contained, enclosed in the mucous membrane, in cysts or minute sacs, worms coiled upon themselves. Each cyst, containing one worm, was best seen by transmitted light. The colon was nearly full of fæcal matter, which contained thousands of parasites scarcely visible. ”

“ They do not touch one another at all and there is no trace of an ectosome or dermal cortex, and hence there are no true inhalant canals, and the water circulates without interruption between the chambers. In the genus Sycon (fig. 14) the walls of adjacent chambers come into contact with one another and fuse together and thus give rise to more or less well-defined inhalant “inter-canals.” The chambers themselves may branch, and in some species of Sycon a thin, pore-bearing dermal membrane connects together their distal extremities and covers over the entrances to the inhalant canals. ”

“ In the length of the incubation period and the comparatively trifling character of the early signs, the germ of syphilis betrays one of its most dangerous characteristics. The germ of pneumonia, for example, may be present on the surface of the body, in the mouth or elsewhere, for a long time, but the moment it gets a real foothold, there is an immediate and severe reaction, the body puts up a fight, and in ten days or so has either lost or won. ”

“ The limits to grafting suggest not that an inappropriate stock does not offer to the protoplasm of the scion the right materials, but that it presents them in proportions and in forms which are unsuitable for the assimilable powers of the latter, or, possibly, mingled with substances poisonous in themselves or capable of becoming so in conjunction with bodies in the scion. ”