Taxonomy of the genus Vulpia (Gramineae). I chromosome numbers and geographical distribution of the Old World species

Three sections of Vulpia (Gramineae: Festuceae) are recognized: Vulpia, Loretia (Duval-Jouve) Boiss. and Spirachne (Hack.) Boiss., containing 11, 8 and 1 Old World species respectively. The chromosome numbers of 16 of these species have been counted, and the results are presented together with a survey of pevious counts and a summary of the known distribution ranges of all the species. A single chromosome number can be allocated to each species; of the 16 species counted 9 are diploids, 3 tetraploids and 4 hexaploids. All the polyploids belong to section Vulpia and are either of wide distribution, or occur only in the northern or eastern parts of the total range of Vulpia, well away from the western Mediterranean which is considered the centre of origin of the genus.