 He later worked at the zoological stations in Naples (1887–88, 1890) and Rovigno (1892-1898).In the late 19th century he journeyed to northern Norway (Tromsø, Sørvær, Trollfjord, Bear Island), where he performed studies of cetaceans.In 1889, he qualified as a lecturer of comparative anatomy, and in 1912, was appointed an associate professor to the museum of pathology at the University of Berlin.