COTTA, BERNHARD VON (1808-1879), German geolo gist, was born near Eisenach, on Oct. 24, 1808. He was edu cated at Freiburg and Heidelberg, and from 1842 to 1874 he held the professorship of geology in the Bergakademie of Frei burg. He was one of the earliest to use the microscope in determining the structure of fossil plants. Later on he studied ore-deposits, rocks and metamorphism. Cotta died at Freiburg on Sept. 14, 1879. Among his many works may be mentioned Geologie der Gegenwart (1866) .