The most violent and deadly form of diarrhea in the newborn calf deserves a special mention. This may appear immediately after birth, and shows itself almost invariably within the first or second day. The most intense symptoms of white scour are complicated by great dullness, weakness, and prostration, sunken eyes, retracted belly, short, hurried breathing, and very low temperature, the calf lying on its side, with the head resting on the ground, lethargic and unconscious or regardless of all around it. The bowel discharges are profuse, yellowish white, and very offensive. As a rule death ensues within 24 to 36 hours. A marked characteristic of this form of illness is that it attacks almost every calf born in the herd, or in the building, rather, and if the calf escapes an attack in the first two or three days of its life it usually survives. Those that recover from an attack, however, are liable one or two weeks later to suffer from an infective inflammation of the lungs. The infection clings to a stable for years, in many cases rendering it impossible to preserve and raise the calves. It has frequently coincided with abortions and failures to conceive in the same herd, so that it has been thought that the same infective germ produces one type of abortion. On the other hand, the removal of the calving cow from the herd to calve in a separate building, hitherto unused and therefore uninfected, usually effects the escape and survival of the offspring. The disease has been traced by Nocard and LigniËres to a small bacillus having the general characters of those that produce hemorrhagic septicemia, which is usually combined with a variety of others, but is in some cases alone and in pure culture, especially in the joints. The theory of LigniËres is that this bacillus is the primary offender, and that once introduced it so depresses the vital powers of the system and tissue cells that the healthy resistance to other bacteria is impaired or suspended, and hence the general and deadly invasion of the latter. Inoculations with this bacillus killed guinea pigs or rabbits in 6 to 18 hours, and calves in 30 hours, with symptoms and lesions of hemorrhagic septicemia, including profuse fetid diarrhea. The predominance of the early and deadly lesions in the alimentary tract would seem to imply infection through the feed, and the promptitude of the attack after birth, together with the frequent coincidence of contagious abortion in the herd, suggest the presence of the germ in the cow; yet the escape of the calf when the cow calves in a fresh building is equally suggestive of the infection through germs laid up in the building. This conclusion is further sustained by the observation that the bacillus evidently enters by the raw, unhealed navel, that it is diffused in the blood, and that a very careful preservation of the navel against infection gives immunity from attack.