The present study on the chromosome cytology of two species of Diplopoda which are commonly called pill-millipedes, is a continuation of a similar study for the group (CHOWDAIAH 1965). They present two diploid chromosome numbers of 26 and 30, and the highest chromosome number (2n = 30) is recorded for the group. In the species studied, all the chromosomes are acrocentric. The sex-chromosome mechanism is of the XY type. The sex bivalent (XY) is the largest pair in the complement. An attempt has been made to gain some evidence on the probable numerical relationship of the various Karyotypes and their role in the evolution of the group as a whole.