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are little worms with rounded ends, and present no indi cations of any internal organs. The male worm is seldom more than two-thirds the length of the female. It presents the same bead-like arrangements as the female, and a reproductive organ whose aperture apparently coincides with the anus; while the female sexual aperture is comparatively near the head-end of the worm. The body terminates with two hooks, doubtless subsidiary to the reproductive process. The males are less numerous and shorter-lived than the females, and probably die after having discharged their natural function. The females continue bringing forth young for two or three weeks. The embryos, according to Leuckart, Cobbold, and all leading helminthologists, penetrate the walls of the intes tine, and pass directly into the muscles of their 'bearers'
Sexually mature female Trichina spiralis (highly magnifled). or 'hosts,' where, if the conditions are otherwise favorable, they are developed into the form originally observed by Owen and Paget. In this way, by proceeding along the course of the intermuscular connective tissue, some reach the muscles of the extremities and other distant parts; but the majority of the wandering embryos (according to Virchow) 'remain in those sheathed muscular groups which are nearest to the cavity of the body (abdomen and thorax), especially in those which are smaller and most supplied with connective tissue.' These embryos penetrate into the interior of the separate muscular bundles, and in the course of 14 days acquire the size and organization of T. S. The surrounding tissues soon become disorganized, and the spot inhabited by the coiledup worm is converted into a spindle-shaped widening, within which the previously described cyst is formed by a hardening and calcification of the exterior. A point of great importance in relation to the distribution of this parasite, and as having a practical bearing on the disease known as Trichiniasis (q.v.), has been established by the experiments of Davaine-viz., that while in the adult condition, trichinæ perish in cold water in about an hour, and cannot survive the decease of their host more than six
hours, the larvæ remain alive in water for a month, and will live for a long time in flesh which has become putrid. In this way, a carcass near a marsh or rivulet may communicate the parasites to the ruminants that drink the water, or to pigs.'
In the same year (1860) in which Virchow and Leuckart proved that by feeding an animal on flesh containing the T. S., intestinal trichina were produced, and watched the transformation of the young of the latter into muscular trichinæ, a very important corroborative medical case was observed and recorded by Zenker. In this case, the patient was a servant-girl, aged 20, and the principal symp toms were loss of appetite, prostration, violent pains and contraction of the limbs, and finally oedema, which, with a certain amount of pneumonia, terminated fatally in a mouth. After death, numerous larval trichinæ were found in her muscles, while the intestinal canal contained sexually mature worms. Three weeks previously, before the girl had become ill, she had assisted in killing pigs and making sausages. It was further ascertained that, a few days before her illness commenced, she had eaten some of the meat in a raw state. On examination, it was found that the pork (both hams and sausages) contained numerous encysted trichinæ. It was ascertained also that the butcher and several members of the girl's family (to whom she had probably given sausages) were attacked with symptoms similar to those which, in her case, proved fatal. How the pig acquires its trichinæ is unknown; but that the larval trichina contained in putrid flesh, etc., may easily gain admittance to the pig's alimentary tract, is a supposition entirely probable. Beet-root, earth-worms, moles, and rats have been suggested as their infectors; but on this subject see the advice given by the French commissioners, under TRICHINIASIS. The adult T. S. is liable to infest the intestinal canal of all animals in which the larvæ have been found in the muscles. In this category must be placed man, the dog, cat, rabbit, rat, mouse, mole, hedgehog, and badger. Whether birds ever contain trichinæ is doubtful: reptiles and fishes are free from this parasite.
TRICHINIASIS, trik-i-ni'a-sis: diseased condition induced by ingestion of food containing Trichina spiralis in large quantity. The first recorded case in the human subject is that of Zenker (see TRICHINA SPIRALIS), but there can be no doubt that the disease has long existed, though its origin was previously unsuspected. (An obscure case had been noted, but not investigated, in England 1835.) The first symptoms in the human subject are loss of appetite, followed by nausea and a sense of fatigue, prostration, and general indisposition: this stage lasts about a week. Pain and stiffness of the limbs, accompanied by swelling of the face, and fever of a peculiar type, charac terized by very frequent pulse, moderate thirst, and copious perspirations, now show themselves; the beginning of the second stage being thus synchronous with the migration of the trichina-brood into the muscles, there to become
encysted. During this stage, pressure, or any attempt to move the parts under the control of the swollen muscles, is intensely painful, and even the normal respiratory movements cause such constant pain as to render sleep impossible. In severe cases, the patient lies on his back like a paralyzed person. The tongue presents much the same appearance as in ordinary gastric fever. The bowels are usually constipated, though in some of the worst cases there is continuous diarrhea. The swelling which began in the face disappears, and is replaced by swelling of the feet, which gradually rises to the trunk. In about the fourth week of the disease, the trichinæ may be regarded as permanently settled, and as having completed their destructive action on the muscles. This is the beginning of the third stage, characterized mainly by extreme weakness. The gastric symptoms abate, the appetite returns, and, in favorable cases, the muscular pains and swelling gradually diminish; while, in severe cases, this third stage is the most dangerous part of the disease; the diarrhea being severe, and accompanied with tenesmus, and often with involuntary discharges of the fæces and urine, while the skin exhibits extreme pallor, and is enormously distended with effused serum. Moreover, pneumonia often supervenes at this period. The fourth and last stage is that of convalescence. This may begin at the fifth week, or later, and may last from three weeks to three months. In mild cases, it is impossible to draw a definite line between this and the preceding stage. Death may occur at any period. It has been observed as early as the 5th, and as late as the 42d, day of the disease. A single trichinous pig, if its flesh is eaten without being previously submitted to such culinary processes as to destroy the vitality of the larval trichinæ, may establish a local epidemic of this disease. The most important of those epidemics have occurred in Germany, and are noticed by a German physician, Dr. Thudichum, in The Seventh Report of the Medical Officer of the Privy Council,' 1865. Of these, the second or great epidemic at Hettstädt was the most severe. It began 1863, Oct., and affected 158 persons, of whom 28 died. All these were found to have been eating trichinous pork, either entirely raw, or in the form of smoked or fried sausage, meat-balls, brawn, black-pudding, etc. only safe rule is not to eat pork in any form unless it is known to be thoroughly cooked. In the United States the disease most often occurs among the German population, from eating raw ham, or sausages containing pork insufficiently cooked.
As soon as a case of suspected T. comes under the notice of the physician, attempts should be made to remove the mature worms from the intestine by active purgation. For this purpose, calomel, in scruple doses, is more serviceable than any other purgative. Two or three such doses should be given at intervals of 24 hours. No special directions can be given for treatment of the fever. If there is any appetite, the diet should be light but nourishing. Liebig's extract of meat has been found serviceable in keeping up
the strength. The most effectual remedy for the sleep. lessness has been the cold wet sheet, in which the patient should be wrapped repeatedly during the day. The preparations of opium only aggravate the discomfort. The other symptoms must be treated by the ordinary rules of therapeutics.
Considering the gravity of this disease, it would be important to be able to decide, during a pig's life, whether it were trichinous or not. On this point there is some difference of opinion; but Professors Delpech and Reynal, charged by the French govt. to report on this disease, assert that the animal, while living, shows no signs of the presence of trichinæ, nor can they be detected in the meat with an ordinary lens, but a powerful microscope renders them at once visible.' In Hanover, out of 25,000 pigs, 11 were found trichinous; in Brunswick, 16 were affected out of 14,000; in Blakenburg, 4 out of 700. The French commissioners assert that a temperature of 167° F. is suffi cient to kill the parasites, and that meat thoroughly salted is also perfectly safe; they advise that smoke-dried sausages, though probably safe, should be well boiled. They further attribute the spread of the disease among pigs to the fact that they are foul feeders, and will eat any offal, such as the dead bodies of rats and other animals, which are known to be liable to the disease. They recommend farmers to be very cautious in feeding their pigs to avoid giving them flesh without first boiling it; to destroy rats and small carnivorous animals, and never to leave human or other excrements in places where pigs can reach them. Finally, they advise all experimenters to burn trichinous flesh when their investigation is completed, and not to throw it away; for a fragment of it might be eaten by a rat, the rat devoured by a pig, and the pig thus become the medium of the disease to man. In 1863, a trichinous pig from Valparaiso, killed on board a merchant-vessel on the high seas, caused the death of two of the crew; and there have been slight local trichinous epidemics in the United States. Probably T. is a common ailment in many countries; its symptoms, except in very severe cases, attracting no special notice, because of their similarity to those of rheumatic disease and acute febrile attacks. Helminthology, and the detection of parasites of all kinds, still require much investigation by the medical profession.
TRICHINOPOLY, trich-in-op'o-li (correctly, TRICHINAPALLI): city, cap. of the collectorate of T., in Brit. India; on the right bank of the Kaveri, 30 m. w. of Tanjur. The fort, which includes the old town, stands on the rugged slope of a steep granite rock, 500 ft. high. The walls of the fort, now demolished, had a circuit of 2 m.; and this area is inhabited by a dense population, dwelling in low, closely packed huts. The streets are crowded at all hours of the day with passengers, bullock-carts, and cattle. Beyond the walls is St. John's Church, containing the tomb of Bp. Heber, who was buried here 1826. The climate during eight months of the year is exceedingly hot; nevertheless T. is the headquarters of the s. division of the
Madras army; there are several barracks, and the lines for the men and the officers' houses cover a space 6 m. in circumference. Cheroots are manufactured in large quantity, from excellent tobacco grown in the vicinity. Manu factures of hardware, cutlery, and jewelry, especially gold chains, harness, and saddlery, are extensively carried on. A railway to Madras was opened 1875.-Pop. (1881) 76,500: (1891) 90,730.-The district of T. has 3,561 sq. m.: pop. (1891) 1,519,306.
TRICHOCEPHALUS, trik-ō-seƒ ̃á-lus [from Gr. thrix, gen. trichos, a hair; cephale, the head]: genus of intestinal worms, of which one species, T. dispar (described by the older writers, who mistook its head for its tail, as Trichuris and Ascaris trichiura), infests the human intestinal canal. Dr. Cobbold describes it as a small nematoid worm, the male 14 inches long, and the female fully 2 inches: it is characterized by an extremely long hair-like head and neck, occupying about two-thirds of the entire length. This parasite is comparatively rare in this country; while, according to Davaine, not less than one-half the inhabitants of Paris are infested by it. Its presence is attended with little or no inconvenience. Its development and mode of access into the body are not yet clear. Davaine finds that the eggs are not developed within the host's intestines, but are discharged per anum, in the immature condition in which they escape from the parent; and it further appears that after their expulsion a period of six months must elapse before embryonic formation commences. As in the more common instance of Ascaris lumbricoides, it is probable that they complete their development in open water, from which they are transferred to the human stomach.
TRICHOGENOUS, a. tri-kōj'ĕ-nŭs [Gr. thrix or tricha, hair; gěnnáō, I produce]: productive of hair.
TRICHOGYNE, n. trik'o-jin [Gr. thrix or tricha, hair; guně, a woman]: a receptive organ concerned in the sexual reproduction of certain algæ.
TRICHOLOGY, n, tri-kõl'ō-ji [prefix tricho-; Gr. logos, a discourse]: the study of human hair, with a view to the prevention of baldness. TRICHOLOG'ICAL, a. trik-ō-lõjʻikal, of or pertaining to trichology. TRICHOLOGIST, n. triköl'ō-jist, one who makes a scientific study of hair.
TRICHOME, n. trik'im [Gr. trichoma-from thrix or tricha, hair]: in bot., any structure, such as a bair, originating as an outgrowth of the epidermis.
TRICHOPTERA, n. tri-kōp'ter-ă [Gr. thrix or tricha, hair; ptera, plu. of pteron, a wing]: a sub-order of neurop terous insects; the caddis-flies (see CADDICE). TRICHOP'· TERAN, a. -tér-ăn, or TRICHOP'TEROUS, a. -us, hair-winged, as the caddis or case-worm flies.
TRICHORD, n. tri kawrd [Gr. treis, three; chorde, a string]: a three-stringed lyre: ADJ. having three strings; said of an improved pianoforte, each note of which has three strings for the greater part of its compass.