1884 enrollment as a student of zoology and medicine at the University of Berlin under F. E. Schultze, Emil Du Bois-Reymond and Rudolf Virchow; 1887 Ph.D. in zoology; studies of medical sciences at Jena, where he met William Preyer, Wilhelm Biedermann and Ernst Haeckel; 1889 M.D. from Jena; assistant and later (1891) university lecturer at Jena; 1895 associate professor at the physiological institute in Jena; 1901 chair of physiology at Göttingen in succession to Georg Meissner; 1902 foundation of the Zeitschrift für allgemeine Physiologie; 1910 replacement of Eduard Pflüger at Bonn; 1911 Silliman lectures at Yale University; research trips to the Mediterranean and Red seas and work at the Zoological Station in Naples under Anton Dohrn.
Degrees
Ph.D. in zoology, University of Berlin, 1887; M.D., University of Jena, 1889