Abstract
1. It has been cleary shown by Prof. T. Morinaga that three Species of genus Panax. viz. P. ginseng, P. quiquefolia, and P. japonicum f. typicum have all 24 chromosomes in their gametic numbers, and there are no special differences in shape among bivalents at meiosis of those three species. These points were confirmed again in the present studies. 2. At meiosis, the pollen mother cells of the F1 hybrids, P. ginseng × P. quinquefolia, and P. japonicum f. typicum × P. quinquefolia, showed in most cases, metaphasic configuration presented as 23II+2I, though rarely 22II+4I was also found. In the F1 hybrids, P. ginseng × P. japonicum f. typicum, the metaphasic configuration was 22II+4I in most cases, and 21II+6I and 20II+8I were also met with rather frequently. 3. From the results above mentioned, it is concluded that the genomes of those species belong to genus Panax are essentially identical, though some differentiation seems to have occurred between the genomes of those different species. The degrees of the differentiation are rather low between those of P. ginseng and P. quinquefolia, and P. quinquefolia and P. japonicum f. typicum, between those of P. ginseng and P. japonicum f. typicum, however, the differentiation seems to be somewhat higher.
