Abstract
This is a preliminary report on the polymorphism of the salivary gland chromosomes occuredng in the natural populations of Drosophila in Hokkaido. Twelve different kinds of chromosomal variations were observed in eight strains from the following five species: D. bifasciata, D. immigrans, D. melanogaster, D. nigromaculata and D. sordidula (Figs. 1-14). Among them, seven types were found to occur in D. immigrans collected in the University Botanical Garden, Sapporo.
