In the genusBeta, chromosomes at pachytene are about 10 times longer than in mitotic metaphase and show a conspicuous differentiation of chromomeres along their arms. It is shown that in sugar beet (Beta vulgaris) these chromomeres are mainly restricted to well defined blocks adjacent to the centromere regions. In the wild speciesB. procumbens, the chromomeres are found not only in the centromere regions, but also occur intercalary. In both species, conspicuous telomeres have not been observed. TentativeFeulgen-DNA measurements revealed that the difference in chromomere distribution between these species is probably not caused by significant differences in DNA amounts. As the patterns observed in sugar beet also occur in other members of the sectionVulgares and those observed inB. procumbens in the other two members of the sectionPatellares, it is hypothesized that the heterochromatin distributions are representative for the sections mentioned.