Article

In the frame of a project conceming the knowledge and the protection of some Mediterranean species, we studi ed, with the techniques of modem cytogenetics, a complex of four closely related taxa of genus Lilium (Liliaceae). All species (L. bosniacum (G. Beck) G. Beck ex Frish, L. carniolicum Bernh., L. pomponium L. and L. pyrenaicum Gouan) be long to section Lyriotypus. They have restricted distribution areas in the Dinaric mountains, the Alps, and the Pyrenees and neighbouring mountains. In spite ofa constant chromosome number (2n = 24) and a very similar karyotype morphometry, the distribution of heterochromatic bands (detected by fluorochrome banding) and the location of 18S-5.8S-26S ribosomal genes (detected by in situ hybridization) allowed us to characterise the karyotypes ofthe different species. Nuclear DNA amount (assessed by flow cytometry) was also determined.