The morphology of hairs in species of Plantago L. sectio Oreades Decne

Abstract

The hairs of three taxa of sectio <em>Oreades </em>Decne genus <em>Plantago </em>have been studied. We have found that hair typical for the majority of representatives of the genus <em>Plantago, </em>that is, with a unicellular stalk and head vertically divided into two cells, occur in these studied taxa. Some of the headless hairs occurring here are similar to those occurring in sectio <em>Arnoglossum </em>Decne. Rahn's (1978) suggestion of transferring sectio <em>Oreades </em>to the subgenus <em>Psyllium </em>seems wrong since the representatives of this section, in contrast to subgenus <em>Psyllium, </em>do not have hairs with the stalks consisting of several cells and unicellular heads, club-like hairs or iridoid-plantarenaloside. They contain, however, hairs with overlapping cells and iridoid-catapol, which is absent in the taxa of subgenus <em>Psyllium</em>.