Cytotaxonomic notes on some Galium species, Galium silvaticum L., Galium aristatum L. and Galium schultesii Vest

The three species Galium silvaticum L., Galium aristatum L. and Galium schultesii Vest show differences in morphology, cytology and geographical distribution. These differences are described and discussed. Crossing experiments between the three species were without results. No hybrid could be obtained. Galium silvaticum, Galium aristatum and Galium schultesii must be considered as separate species.