The present volume contains papers presented on the occasion of the Ichthyological Symposium on Genetics and Mutagenesis held on October 13 through 15, 1972 at the Biology Institute of the Association for Radia- tion and Environmental Research in Neuherberg near Munich, Germany. These symposia have been held annually since 1955 by former students of Prof. C. Kosswig and Prof. F. Anders in Hamburg or Giessen. In the last two years attendance has increased beyond the national German basis, but the Neuherberg meeting of fish geneticists was the first that could be called "international", the...