This disease is characterised by extensive inflammation, affecting the entire mucous membrane of the large intestine, by more or less extensive ulceration of this bowel, the ulcers being covered with muco-fibrinous patches rich in coccidia, by localisation of the parasites in the epithelial cells of the glandular cul-de-sac, by the appearance of the disease at a special time of year and in special districts, where it assumes the form of an enzooty, and by the fact that it always appears in the same pastures. The mortality varies between 12 and 25 per cent. from year to year. =Microscopic appearances.= The protozoa which produce this disease assume the form of ovoid cysts, varying in length from 18 to 25 µ, and measuring at the widest part about 13 µ. They possess a hyaline envelope whose existence is proved by its double contour line, and yellowish, granular, highly refractile contents. This granular material does not always occupy the whole of the cavity. At a certain stage of development it collects towards the centre, forming a nucleus and leaving clear spaces at the poles of the cell. At a later stage this nucleus divides into four portions which afterwards separate. =Treatment.= The protozoa, in their cystic condition, are very resistant to destructive influences. The most common natural cause of their destruction is drying in the open air. Unfortunately, in the localities where the patients usually live, that is, filthy byres, wet pasturages, etc., this destruction only takes place to a very limited extent. The disease can be attacked by prophylactic and therapeutic measures. Prophylaxis consists—firstly, in destroying the parasites contained in the dejections by the free use of 3 per cent. sulphuric acid solution; and, secondly, in removing the young animals from infected fields during the months between June and September. Therapeutic treatment comprises—firstly, stimulant applications to the abdomen; secondly, disinfection of the intestine by the administration of salol, benzo-naphthol, very diluted solutions of creolin, etc.; thirdly, intestinal irrigation by the administration of mucilaginous drinks containing bicarbonate of soda, supplemented by general tonic treatment and the supply of concentrated, very nourishing, and easily digested food (Degoix, _Revue générale de Médecine Vétérinaire_, No. 28, February 15th, 1904, p. 177). * * * * * McFadyean describes a similar disease to the above in two to three months old lambs (_Jour. of Comp. Path. and Therap._, March, 1896, p. 31). The mortality reached 10 per cent. The lambs at the time the disease broke out in the flock were closely folded together with the ewes on growing roots, which, needless to say, were much soiled with earth and fæces before they were completely consumed. INTESTINAL HELMINTHIASIS IN RUMINANTS (Ox, Sheep, Goat). [Illustration: $1]