The translators' note makes clear the contribution of Tawara (1873-1952) to clinical medicine by his systematic investigation of normal and pathological hearts in mammalian species, though controversies continue over the precise anatomic substrates for atrioventricular conduction and its abnormalities. Includes a facsimile cover of the original German monograph (Das Reizleitungssystem des Saugetierherzens, Gustav Fischer); Aschoff's foreword to the 1906 edition; photos of Tawara and Aschoff; and five tinted plates with transparent overlays of human, dog, sheep, and bovine hearts. Distributed by World Scientific. Annotation copyrighted by Book News, Inc., Portland, OR