The course of meiosis, including an analysis of chromosome configurations, is described for five diploid × diploidVulpiacrosses, five tetraploid × diploidVulpiacrosses, one hexaploid × diploidFestuca×Vulpiacross, one tetraploid × hexaploidVulpia×Festucacross, and one hexaploid × hexaploidVulpia×Festucacross. In most cases there was 97.5 or more pollen sterility, but two heptaploid plants obtained (presumably by non‐reduction) from a hexaploid × diploid cross had about 60 stainable pollen. In the diploid hybrids pairing was quite extensive, and inV. ligustica×V. geniculatait was more or less as in the parent species (mode 7 bivalents, with regular separation). In the triploid hybrids the modal situation was 7 bivalents + 7 univalents, but evidence concerning the genomes which were pairing was equivocal. Evidence from the crosses at higher ploidy levels shows that both homogenetic and heterogenetic pairing does occur, although the relative amounts are uncertain. The results in general support the current classsification ofVulpia, except that they suggest the removal ofV. alopecurosfrom sec
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