1. In this report, the number and relative sizes of chromosomes are described in 5 species from Bangkok. 2. It is noteworthy that the karyotype has supernumerary chromosome in Moduza procris (n,35,36) from Bangkok. 3. Mycalesis mineus (n,16,17,18) from Bangkok shows a polymorphism of the karyotype at the primary spermatocyte.
