The principal letters in this collection are to Otto L. Mohr and concern problems and progress in genetics, the Nobel Prize, and some account of Mohr and his family under the Nazi occupation of Norway, 1940-1945. Included with this group is a partial biographical essay on Calvin Blackman Bridges.

In 1912, the University of California, Berkeley, became the first university in the nation to form a separate Department of Genetics. The first two appointments in the department went to plant geneticists Ernest Brown Babcock and Roy E. Clausen, and as the department grew slowly, shifting slightly away from its roots in agricultural science, it gained a strong reputation as an important center for research in several areas in genetics and evolutionary biology. The U.C. Berkeley Department of Genetics Collection contains a selective sampling of correspondence relating to the organization and early history of the nation's first Department of Genetics. Centered in the years 1912-1930, the collection consists primarily of correspondence to and from Babcock and Clausen, pertaining to their research, administrative matters, and the genetical community. Prominent among their correspondents are George H. Shull, Thomas Hunt Morgan, A. H. Sturtevant, and H. J. Muller.