Five species of worms inhabit the human bowels-the round worm, the thread worm, the long thread worm, the common tape worm, and the broad tape worm.

The round worm very much resembles the common earth-worm. The thread worm resembles small pieces of thread, from which it has derived its name. The long thread worm is an inch or two in length, and consists of two distinct portions; one of which, constituting two-thirds of the whole length of the animal, is scarcely thicker than a horsehair, the other and shorter portion is very much thicker. The long tape worm varies from five or ten feet long to as much as sixty feet long, and, it is said, has even reached a hundred feet. The broad tape worm is, as its name implies, broader than the long tape worm. The round worm, thread worm, and long thread worm have the separate sexes in different individuals, but the tape worms have only one sex, or both sexes in one individual.

Worms in the alimentary canal frequently produce great disturbance in the system, uneasiness or pain in the stomach and bowels, sometimes gnawing or biting, and sometimes indescribable, yet very distressing, Sometimes a sense of itching at the fundament and at the nostrils. The bowels are often disordered, sometimes confined, at other times relaxed, with mucous or bloody discharges, as in dysentery. The mucus is sometimes in shreds or flakes, which are not unfrequently mistaken for fragments of partially digested worms. Frequently portions of undigested food will pass with the motions. The appetite is very uncertain; in some cases natural, in others poor, craving or depraved. The belly is often swollen, hard and tympanitic, the breath unpleasant, and the tongue furred, with a disagreeable taste in the mouth. Swelling of the upper lip, bleeding from the nostrils, and grinding of the teeth during sleep are frequent symptoms.

But the effects of worms are not confined to the alimentary canal; various derangements of health are experienced in consequence either of the direct irritation of the worms, or of the disordered digestion which they occasion. Among the most common of these are nervous affections, such as fretfulness, irritability of temper, wakefulness or drowsiness, disturbed sleep, sudden starting out of sleep as if from fright, giddiness, headache, spasmodic movements of the eyelids, impaired vision, singing in the ears, and partial deafness. Convulsions are not unfrequent in children, and symptoms strongly resembling those of water on the brain have been ascribed to worms, and have ceased on their removal. In addition to these symptoms, obstinate cough, shortness of breath, palpitations, hysteria, and a general disturbance of the system, marked by a languid circulation, sallow skin, sunken eyes, dark circles around the eyelids, and general emaciation. Persons in apparently perfect health are occasionally affected with worms, which give no signs of their existence until they are observed in the ordinary passages, or are expelled during some acute attack of disease, either by the medicines employed, or the influence of the disease itself; and it is no uncommon event to find worms in the bodies of individuals after death, who have shown no signs of them during life. Hence, some persons have inferred that they are generally, if not always harmless, and some have even gone so far as to contend that they perform a useful office, being intended as scavengers to clear off the noxious matters contained in the bowels. But these opinions are opposed to general experience.

Worms are very seldom fatal. It has been supposed that worms are capable of piercing the intestines, and a case is on record in which a portion of the gut had been pierced in numerous places by the long thread worm. In most cases, however, in which worms have been found in the cavity of the abdomen, they are supposed to have escaped through holes in the stomach, which may have been produced by the action of the gastric juice after death.

The cause of the presence of worms in the alimentary canal has been a matter of dispute. Their growth is evidently favoured by an unhealthy condition of the stomach and bowels, and particularly by a feeble or disordered state of digestion. Hence persons of sedentary habits, of scrofulous tendency, and of general bad health, are apt to be affected with them. It is supposed that over-loading the stomach beyond the powers of digestion is favourable to their growth. The use of unripe fruits and raw vegetables, and indigestible substances generally, predisposes to worms, as well as bad bread, spoiled cheese and meats, the flesh of diseased animals, and the use of bad water. It has been observed they are most abundant in moist countries, and during a long prevalence of warm, damp weather. Children, after weaning, and up to or about the age of puberty, are more frequently afflicted with worms than either very young infants or adults, probably owing to the nature of their diet.

Treatment

In treating a patient afflicted with worms, we have two objects in view-first to get rid of the worms already in possession, and, secondly, to prevent the occupation of the bowels by a fresh crop. In the first place, in order to dislodge the worms, we may give a dose of India Pink and Senna Tea (the former is commonly called Pink Root, but, in reality, the whole plant is used) mixed together; this may be given in the morning before breakfast, and repeated every second morning for two or three times. In most cases, these will be sufficient. Where an additional anthelmintic is required, turpentine has been found very efficacious.

Half an ounce of Indian Pink may be mixed with half an ounce of Senna; a pint of boiling water may be poured on them, let it stand for two hours; then strain. A child of two or three years old may take from one to two tablespoonfuls for a dose, and other ages in proportion.

A favourite medicine for the removal of thread worms, particularly in America, is santonin, the active principle of a species of wormwood. From two to eight grains, according to the age of the patient, (8 grains for an adult), may be given at night; followed the next morning by a dose of Senna Tea. Santonin will sometimes produce unpleasant symptoms; it will occasionally affect the sight, causing everything to appear of a yellow colour; it also gives an orange-red tinge to the urine. Three or four grains of Santonin mixed up with a small piece of soap, introduced into the bowel every night at bedtime, is said to have been very effectual in expelling the thread worms.