In the literature about 60 taxa have been described at various taxonomic levels in the wall barley – sea barley group. Considerably less confusion exists between wall and sea barley than within. It appears that five taxa have been recognized and are likely to be valid, but there has been disagreement as to their status. The authors have investigated new micromorphologic characters and reexamined and critically defined traditional characters of material collected throughout the area of the natural habitats of the group. Characters taken from the seed epiblast and the floral lodicules were found useful for conclusively distinguishing between Hordeum murinum (sensu lato), H. glaucum, and H. marinum (sensu lato). Exploratory data analysis of 35 other characters investigated supports this distinction. Thus, in this particular paper three taxa are tentatively recognized. In the subsequent paper the validity of the three taxa will be tested by numerical analysis, and furthermore the possibility of five taxa will be investigated and similarly tested.
Elementary stabilizer limits of irreducible group characters
