Otto Bütschli

Bütschli, Otto 

Born May 3, 1848, in Frankfurt am Main; died Feb. 3, 1920, in Heidelberg. German zoologist. Bütschli studied mineralogy, chemistry, and zoology in Karlsruhe, Heidelberg, and Leipzig and from 1878 was a professor at the University of Heidelberg. He worked in the areas of cytology and protistology. He advanced the theory of a cellular or frothy structure of protoplasm and methodically researched the stages of meiotic cell division and the processes of fertilization in animals. He attempted to explain the origin of asymmetry in the structure of gastropod mollusks and five-pointed symmetry in echinoderms. He was the author of the fundamental compendium The Simplest Animals (vol. 1, parts 1-3, 1882-89) and Lectures on Comparative Anatomy (vols. 1-6, 1910-34).