The diagnostic value of the Wassermann test for syphilis performed on sera from human blood taken post mortem has been the subject of investigation and discussion for the last ten years. Practically all published reports on the work have been made in Germany. The first to carry out this research, Much and Fraenkel (1) and Pick and Proskauer (2), concluded that the Wassermann reaction gave reliable results when done on post mortem blood and that the results confirmed the prevailing comprehension of fibrous meso-arteritis, aneurism of the aorta, etc., as syphilitic lesions. Later investigators, on the contrary, arrived at different conclusions. Beside others, Krefting (3), de Besche (4) and Von Bruck (5) decided against the employment of the Wassermann reaction on post mortem blood because they found a very considerable number of positive reactions in cases where not the slightest probability of the existence of syphilis was apparent.