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The concern of the present analysis is the hypothetical ‘cryptopolyploidy’, a concept basically of historical interest only, but discussed again by Battaglia (1996) in a recent treatment of the term and its historical background. Melinossi (1935), while reanalyzing erratic observations on the crucifers Bunias erucago and B. orientalis by Jaretzky (1928a), found 2n = 14 in both species but twice the chromosome volume in B. erucago compared with B. orientalis. Melinossi considered ‘cryptopolyploidy’ in B. erucago, i.e., she discussed pairwise fused chromosomes on a tetraploid basis or endoreduplicated (and thus binemic) chromosomes in this species. Cryptopolyploidy has also been claimed by Pannocchia-Laj (1938) in Vinca difformis ( Vincaceae). Battaglia (1996) criticized the term ‘cryptopolyploidy’ because, in his opinion, the genuinely polyploid status of these plants is not hidden (‘crypto’) but phenotypically (from herbarium specimens) recognizable. He coins the term ‘phenopolyploidy’, i.e., “phenotypic polyploidy disagreeing with the karyotype numerically evalated”. We measured genome size of B. orientalis and B. erucago (both 2n = 14) by Feulgen densitometry and propidium iodide flow cytometry. Surprisingly, B. erucago (the annual species with 2.13 pg, 1 C) turned out to have only 0.81-fold the DNA amount of B. orientalis (the perennial species with 2.64 pg, 1 C). Therefore, any kind of genetically polyploid status in B. erucago is out of the question. Only speculative significance can be ascribed to the terms ‘cryptopolyploidy’ and ‘phenopolyploidy’. [ABSTRACT FROM AUTHOR]