Results are reported on the production of banding patterns stained with Giemasa. They are obtained from the application of different dyes and dye mixtures to metaphase chromosomes which were pretreated in various ways. The discussion of our findings in addition to those of other authors allows the following conclusions: 1. Alterations of the DNA-protein complex determine the production of all banding patterns stained with Giemsa. 2. In addition to the accordance between base ratio of the DNA and banding pattern, there exists a base specific attachement of qualitative different non-histone proteins to DNA.