RHIZOIDAL TUBERS AND PROTONEMAL GEMMAE IN EUROPEAN DITRICHUM SPECIES

The occurrence of rhizoidal tubers and protonemal gemmae in European D itrichum species is described in plants collected in nature and compar ed with protonemal gemmae and tubers obtained in agar culture. Rhizoid al tubers are reported for the first time in D. pallidum, D. plumbicol a, D. subulatum and D. zonatum and earlier reports on tubers in D. cyl indricum, D. comubicum, D. heteromallum, D. lineare and D. pusillum co nfirmed. Based on the occurrence and morphology of tubers, the Europea n species of Ditrichum may be subdivided into four groups.