In seven to eight months the cysts undergo degeneration, the liquid is absorbed, and calcium salts are deposited throughout the mass. The lesions which remain have, in the ox, the appearance of interstitial disseminated tuberculosis. There is no curative treatment. The infested animal recovers spontaneously with the lapse of time, for the cysticerci undergo degenerative processes, but the flesh of such animals is of little commercial value. From a preventive standpoint we can only hope to improve matters by a gradual and progressive change in social and public hygienic conditions. [Illustration: $1] When the life of the nomad shall have been entirely replaced by that of the highly-civilised European and private hygienic precautions have rendered it impossible for animals to obtain access to segments or eggs of the _Tænia saginata_, beef measles will disappear. At present, in the countries where the disease is common, one experiences a feeling of astonishment that it is not far more frequent; for experiment has shown that a person infected with one unarmed tapeworm expels with the fæces an average of four hundred proglottides per month, each proglottis or segment of the worm containing about 30,000 eggs, each of which is capable of developing into a tapeworm. Beef measles is rather common in Germany, but rare in France, Switzerland, and Italy. TRICHINIASIS—TRICHINOSIS. Trichinosis is a disease caused by the entrance into the body of the _Trichina spiralis_. This parasite is swallowed in the larval form, and undergoes sexual changes in the intestine, at first producing intestinal trichinosis, which represents the first phase in the development of the disease. The trichinæ breed rapidly. The embryos penetrate into or are directly deposited in the blood-vessels, which convey them to all parts of the body, thus setting up the second phase of the disease, known as muscular trichinosis. [Illustration: $1] [Illustration: $1] Trichinosis as a disease has long been recognised. Peacock in 1828 and J. Hilton in 1832 mentioned the existence of the cysts of trichinæ; Owen in 1835 gave the name of _Trichina spiralis_ to the parasites contained in the cysts. Trichinosis being common in Germany at that time, Virchow and Leuckart undertook its investigation, but mistook other nematodes of the intestine for the _Trichina spiralis_. In 1847 Leydy recognised that trichinosis occurred in American pigs. In 1860 Zenker found muscular and intestinal trichinosis on post-mortem examination of a girl who had been suspected of suffering from typhoid fever, and a carefully conducted inquiry revealed the fact that this girl had some time previously eaten a quantity of raw ham. Virchow and Leuckart returned to their investigations, and the life history of the parasite soon became definitely known.