The beef tape-worm has been found very prevalent in the cattle of the North-west Pro vinces of India. This was traced in one case to the bad drinking-water supplied to the cattle, sewage, containing the seeds of the tape-worm, being found in the tank from which many of the cattle were watered. The cattle belonged to the army commissariat, and if a barrack cook did not thoroughly cook the meat, tape-worm might have been given to many of the soldiers.
Bothrloeephalus latus (Broad —This variety of tape-worm is not common in Britain. It has been called the Irish Tape worm, though it is commonest in the cantons of West Switzerland and their neighbourhood. It is common also in Russia, Sweden, and Poland. It was at one time very common in Geneva, but seems now comparatively rare there. This change is said by Van Beneden to be due to the fact that whereas, formerly, the water-closets were made to empty themselves into the lake, where the embryos were hatched, and so in fested persons who drank of the water, now the refuse of_the towns along the lake is col lected for manuring the land.
The fully-developed tape-worm is of great ength, more than 25 feet, and is estimated :o possess as many as nearly 4000 oints. The joints, however, are hot so long as those of the kinds already considered, but are much broader, and they do not separate from one another so readily as those of Tcenia solium or medioca Pzellata. The head is club-shaped, without suckers or booklets, but having a long slit-like groove on each side. A highly-magnified new of one side of the head is given in Fig. 118. The features )f this tape-worm are, then, its great length, its very numerous, aloft, but broad joints which are closely packed, and its club-shaped head. Each egg is inclosed in a brownish shell, and the )f the eggs gives to each segment brownish-yellow colour, specially towards the 'entre of the segment, where is the aperture from which they escape. In Tcenia solium it s to be noted this aperture is at the side of the segment.
The natural history of the broad tape-worm is not so thoroughly known as that of the varieties already described. It seems, how ever, to pass through stages precisely similar to other tape-worms. That is to say, the fully developed head, or scolex, throws off joints (proglottides) containing eggs. The eggs pro duce embryos which develop into the embryos with boring apparatus for tearing their way into the tissues of an appropriate host. The flesh of this host, improperly cooked and eaten, will give rise to the fully-developed tape-worm in the alimentary canal of the person who has eaten it. The embryo liberated from the egg is ciliated, that is, covered with long fine hairs.
From the ciliated embryo the boring embryo is produced. In what animals these intermediary stages are realized is not known with certainty. Cobbold believes it is certain fresh-water fish, of the salmon and trout family, as suggested by a German observer, in which the embryos are developed. According to Van Beneden, how ever, the tape-worm passes from man to water " under the form of an egg, or of a proglottis, and from the water to man in the shape of a ciliated embryo. In this manner it is intro duced with the water that is drunk." There is still a fourth variety of tape-worm, that must be described, which is found in man, not, however, in the adult condition, but in one of the preliminary stages, the Tcenia echino coccus, namely. It differs in so many respects from those already described that it will be better to discuss the symptoms and treatment of the latter before going on to consider it. Those that have been considered are the chief tape-worms found in the adult condition in man. There are many other varieties of tape worm, however. Thus in the flesh of the rabbit is the cyaticercus stage of a worm that attains its complete development in the dog. In the brain of sheep, infected with the disease called "gid", is an immature condition (the cause of the disease) of the trenia of the wolf. The tmnia that infests the cat has previously lodged in the mouse or rat. Almost all birds nourish large ttenim. "Woodcocks and snipe always have their intestines stuffed full of ttenia and the eggs of these worms. Every bird contains them by thousands. Fortunately we cannot be infested with the trenia of the snipe and the woodcock." The symptoms of tape-worm.—The usual symptoms that give rise to a suspicion of the presence of worms in the intestinal canal are olicky pains and irregularity of the bowels, licking of the nose, grinding of the teeth during Jeep, bad or capricious and sometimes vora ious appetite, increasing thinness of body, oulness of breath, itching of rectum and fun lament, sickness, dizziness, headache, nervous rritability, and a tendency to faintness, &c. iCet worms may be present without any of these igns manifesting themselves. On the other utud, the presence of worms may give rise to Ither symptoms of a very serious kind which 'et do not in any way indicate their cause. for example, the irritation of worms may voduce convulsions or attacks of St. Vitus' lance, specially in children, and may occasion iysterical attacks in women. Cases are on •ecord of tape-worm producing insanity, epi epsy, paralysis, blindness, and squint.