Carefully conducted epizootic researches in our province have led me to the discovery that a single, native, mountain breed of cattle, that of Vogelsberg, was probably free from tuberculosis as late as twelve years ago. Through imported cattle the tubercular infection was then introduced. But even now the percentage of animals responding to the tuberculin test is about one-quarter that of other breeds. What is curious, however, in these cattle is, that whereas, according to common experience in all other breeds, the percentage of reacting animals increases with their age, in these Vogelsberg cattle the percentage from the fifth year on even decreases. This may depend on the smaller number of animals infected five years ago. Some of the exceptions, however, I must account for by the definite healing of lesions and a consequent disappearance of the reaction. The favorable termination of the tuberculosis in these Vogelsberg cattle I ascribe to the smaller accumulation of the tubercular virus in the still relatively little-infected stables, or, what amounts to the same thing, _to a smaller dose of the virus infecting the suckling calves. These, of course, take up the infecting agent not only from the mother cow, but also from the other cattle._ One can plainly see how the percentage of reacting cattle in this Vogelsberg breed increases from year to year, and I feel certain that ten years hence these cattle will be as badly off in this respect as other breeds, provided measures are not taken to check the advancing infection. Such measures we have had at our command for some time, and their usefulness has been thoroughly proven. I know of a large number of herds which, by means of Bang’s rules, have been made free from tuberculosis and kept so. It is, however, an expensive procedure and requires the constant supervision of an expert, and even then is usually possible only on large estates where any reacting animal may immediately be separated from the unaffected herd. When, therefore, I published a method of protective inoculation against tuberculosis, one which I had proved in my own stables, I was pleased with the spirit of hearty cooperation shown by the owners of large dairies who had already experimented largely with Bang’s procedures.