sent directly to their destination, or if to a market, for purposes of sale, it should be well apart from that used for fat swine, and the loading banks, chutes and yards should be entirely distinct and should be thoroughly disinfected on every occasion after use. The millions now lost yearly from swine epizoötics might well warrant the inconvenience and expense entailed by such precautions. Heavy penalties should be imposed on those shipping pigs from infected localities, on those making false certificate, and on all who in any way violate the law. Independently of State or local authorities the stock owner can do much to protect himself. He can make a number of pens large enough to hold 2 or 3 pigs each, safely fenced off from one another and so constructed that no drainage can take place from pen to pen. Then in winter in the absence of flies, and with rats, mice, and birds excluded the opportunity for the extension of infection from pen to pen can be kept at its minimum. All pigs must be kept apart from the manure heap, and in summer the manure must be so treated as to destroy the larvæ of flies. All food and water that might convey infection must be guarded against. Then if one pig is attacked it will only be necessary to destroy it and its two fellows in the same pen, and even if those in adjacent pens are killed or quarantined the loss will be a trifle as compared to the ruin of the whole herd, as usually happens. Prompt disinfection of the pens and manure is imperative, and the same would apply to the person and clothes of the attendant, and to all stable utensils. _Immunization_ by injection of _sterilized products_ of the bacillus, has not proved satisfactory. In 1880 I applied this to two pigs, causing a transient fever, after recovery from which, the subjects resisted exposure to infected pens and pigs, and even virulent inoculations. But they failed to thrive well. Later experiments by Drs. Salmon and DeSchweinitz respectively, also proved unsatisfactory. The latter separated and injected the enzymes, but lost 50 per cent of his cases, the survivors proving immune, with the drawback of troublesome local lesions. The enzymes obtained from cultures in milk could be used safely on guinea pigs in the dose of 0.01 grams and in some cases even up to 0.04 securing immunity. But the great risk of an overdose, the frequent local lesions, and the subsequent unthrift, have prevented the adoption of the method. _Disinfection._ The experiments of the Bureau of Animal Industry show that, apart from freezing, _four months in the soil_, serves to render the bacillus harmless. From .75 to 1 per cent of quick lime added to soil in the form of lime water, destroyed the virulence in 11 days.