EN
The karyology of representatives of morphologically differentiated taxa within the Caltha palustris complex was studied. Examination of plants from ten populations of C. palustris subsp. palustris from Poland indicated the domination of somatic chromosome numbers 2n = 32 and 56, with 2n = 32 and 56 for var. palustris, 2n = 56 for var. radicans and 2n = 56 for var. cornuta. C. palustris subsp. laeta from the Tatra Mts. had chromosome number 2n = 62. Mixoploidy was characteristic of the material, with a range of euploid and aneuploid chromosome numbers from 2n = 25 to 2n = 94. Only three plants (from Mrzeżyno, Duninowo and Olkusz) uniformly had 2n = 32. Detailed biometric analyses seem to point to the lack of a simple relation between karyological and morphological variability in representatives of the C. palustris complex occurring in Poland.