SUMMARY
The chromosome complements of 2 species of birch mice and 15 species of jerboas represented by the subfamilies Sicistinae (2 species); Cardiocraniinae (1); Allactaginae (9); Dipodinae (5) are described. The diploid number of 13 species of Dipodidae is 48 excluding S. crassicauda (2n = 46) and Sc. telum (2n = 58).
Intraspecific karyotype stability in Allactaginae were Found. Karyotypical similarity has been revealed among the jerboas: the chromosome complements of 3 species of genus Allactaga (jaculus—severtzovi—saltator) are undistinguishable; Pygerethmus platyurus, P. vinogradovi, P. zhitkovi, Alactagulus acontion also do not differ from each other. On the basis of constant chromosome number and the slight variability of FNa it is concluded that pericentric inversions have played the main role in the evolution of jerboas rather than Robertsonian fusions which is characteristic of other groups of mammals. It is suggested that cytogenetical mechanisms do not play any significant role in the reproductive isolation between the sympatric species of this family.
On the basis of karyological and morfological data a somewhat modified classification of the superfamily Dipodoidea is proposed.