As is seen from the above short summary of the views of Norwegian investigators, some maintain the non-specific origin and heredity of the disease; one only, the non-specific origin; one a specific cause and no heredity; and finally, one a specific cause, contagiousness and heredity. It is rather remarkable that supporters both of the specific and the non-specific origin of the disease should regard it as hereditary. It apparently struck none of them that possibly the specificity of a disease, that is, its development through the action of a poison, might be incompatible with heredity. Since the discovery of the Lepra bacillus and its recognition in all leprous products, it is now everywhere admitted that it is the cause of the disease, and it would therefore be superfluous to indicate which of all the symptoms of the disease point to its specific nature. All this was shown in a communication made by one of us to the Copenhagen Congress in 1884. We start then from the assumption that Leprosy is a disease caused by the Lepra bacillus, although it is as yet not strictly scientifically proved, since inoculation on man and animals has not been definitely successful. The question as to heredity now is, Can the lepra bacillus be conveyed by heredity. This is Baumgarten’s view; he holds that both Tuberculosis and Leprosy are thus spread, that the bacilli of both diseases may be transferred to the children and there remain dormant, but that they can thence be conveyed to another generation, and from it to a fourth, fifth, etc. generation, and then in the third, fourth, etc. generation become once more active and cause the disease. We see at once that this is only a modification of Biedenkap’s heredity, a peculiarity of the organism which finally becomes evident as Leprosy. In place of his undiscovered peculiarity, we have undiscovered latent bacilli. Baumgarten’s view is therefore only a hypothesis for the explanation of the origin of the two diseases. The hypothesis may be tested from two points of view: first, we may sift it theoretically; and secondly, we may investigate whether it can explain the distribution of the disease.