EN
The rate of seven meiotic stages (zygotene-pachytene, diplotene-diakinesis, metaphase I, anaphase I, metaphase II, anaphase II, and quartet) was studied in the jerboas Jaculus jaculus jaculus, Jaculus orientalis, and Allactaga tetradactyla, chiasma frequency and terminalization being examined only in J. jaculus and J. orientalis, and compared with the previous data concerning A. tetradactyla. Significant differences in the rate of meiosis, frequency of bivalent types, and frequency of interstitial and distal or terminal chiasmata per genome length were observed between A. tetradactyla and the two congeneric species J. jaculus and J. orientalis. Differences of these parameters among individuals within each species are also discussed in detail.