抄録
The chromosome numbers in somatic cells of six species of Lysimachia are determined by the writer as follows: L. clethroides 2n=24, L. acroadenia 2n=24, L. Fortunei 2n=24, L. japonica 2n=20, L. mauritiana 2n=20 and L. sikokiana 2n=60. They can be devided into two groups with respect to the basic chromosome number: one is the group having chromosome number b=12, while the other is the group with b=10. The size and shape of the chromosomes in the species belonging to the former are generally similar each other, while those of latter are different from species to species.
