 After the sudden death of Naville in 1937, German hydrologist and zoologist Curt Kosswig took over the department.During his 15-year-long scientific research on the fauna of Anatolia, he collected examples of mammals, birds, reptiles, frogs, fish and various invertebrates, which he brought in the museum contributing to its enrichment.In 1957, the top floors of the building were demolished, in which the museum was also situated.