In March 1876 he earned his PhD from the
University of Jena, and two months later became habilitated as a
privat-docent of
zoology at the
University of Bern. From 1878 to 1885 he was stationed at the
Zoological Station in Naples, where he conducted research on wildlife native to the
Gulf of Naples. In 1889 he became a professor of zoology and comparative anatomy at the
University of Zurich and the
Eidgenössische Polytechnikum as well as director of two institutions' zoological collections. From 1898 to 1900 he served as
rector at the University of Zurich. In the autumn of 1891, a European fellowship for the best graduate in class enabled American experimental biologist
Lilian Vaughan Morgan to go to Europe and study muscles in
chitons at the
University of Zurich with Arnold Lang. Norwegian biologist
Kristine Bonnevie studied under Arnold Lang in Zürich in the years 1898-99. Lang sponsored the PhD work of
Marie Daiber, a German-born Swiss zoologist who became a full professor at University of Zurich. He also taught zoologist
Emily Arnesen and philosopher
Heinrich Schmidt. == Works ==