Effusion is usually found in the pleura, clear, grayish or bloody, with flocculi and false membranes, and further branching redness of the serosa. The mediastinum may be thickened by exudate especially around the glands, œsophagus and blood vessels. The lung shows lobular, interlobular and peribronchial exudates approaching at times to the appearances shown in lung plague, along with the atelectasis, emphysema and, in prolonged cases, caseation. Less constant are congestions and petechiæ of the pericardium, heart, kidneys, vesical mucosa, testicles, ovaries or womb. The blood is dark and forms a loose coagulum. In case of abortion the umbilical cord is infiltrated and the placental membranes ecchymotic. The brain and spinal cord and their membranes are sometimes congested and infiltrated and a serous effusion exists in the arachnoid. The bacterium is found more or less abundantly in each of the morbid lesions. _Prevention._ Absolute seclusion of the sick and of all their products is the prime essential. The general distribution of the lesions throughout the body and the uniform presence of the bacterium in the lesions indicate that no part of the body and no secretion can be considered as free from infection. All parts of the body, all expectoration, saliva, fæces, urine, milk even must be withheld from all other animals, at least until they have been thoroughly cooked or disinfected. Manure must be burned, or buried deeply in quicklime. Contaminated pens, yards, wallows, streams and fields must be abandoned or thoroughly disinfected. Galtier found that the virus remained active for six days in putrefying organic matter at 39° to 75° F.; in 25 days in water, at room temperature; the refuse litter, fodder, manure, and drainage matter from the infected place must be carefully guarded against. The virus steadily loses in force in such media, but remains infecting to animals injected with it. The most active disinfectants may be used on the pens and yards (copperas 5%, sulphuric acid 2% solution, or mercuric chloride .2%) while the contaminated fields should be abandoned for the season. All droppings may be treated with sulphuric acid (2%), creolin, lysol, phenic acid or copper sulphate. The susceptibility of practically all the animals of the farm, demands the exclusion of these, while that of rodents, renders necessary the further exclusion of wild mammals; and we may add birds, wild and tame, and if possible flies. The plowing of the contaminated soil will do much to obviate danger, yet the sheep folds and pastures should be separated by a considerable distance from any place where infected animals and objects have been. If drinking troughs for sound animals have been used by the sick or suspected they should be emptied and washed with a disinfectant (sulphuric acid 2:100). ULCERATIVE (ERYSIPELATOID) INFECTION OF THE LIMBS IN CATTLE AND SHEEP.