Abstract
1. The author could determine the chromosome numbers of Japanese bamboo of 8 genera including 13 species as shown in the preceeding table.
2. According to the results of observations of this study together with the author's previous paper (Uchikawa 1933), Yamaura's paper (Yamaura 1933) and Hunter's paper (Hunter 1934), it is certain that most species of Japanese bamboo have the chromosome number of 2n=48, and only a few 2n=54, 2n=72. The latter number is found only in Bambua species. The numbers 48, 54 and 72 are multiples of 6. It is, therefore, assumed that the basic chromosome number of bambuseae is 6.
3. Phyllostachys reticulata KOCH is sterile. It has normal 24 bivalents in P.M.C., and its pollen grains and ovaries are normally developed. As it is propagated asexually, the phenomenon of the sterility in Phyllostachys reticulata KOCH can be explained by self-incompatibility.
