Discusses geographic distribution of tuberculosis and possible explanations for disease-free areas and populations.

Does not think a local population with some distinct physiological character can properly be designated as a race. Thinks local conditions, not natural selection, responsible for such characters. Ernst Haeckel agrees. Asks CD’s opinion.

Encloses article on local immunity to tuberculosis. Has he interpreted CD’s views correctly? Believes the immunity notable in areas like Iceland or mountain areas is due to local conditions, not natural selection. Describes his sanatorium in mountains of Silesia and medical criticism of his work.