Abstract
The Dryopteris dilatata complex in the Caucasus, Siberia and the Far East was studied on the herbarium material from the Komarov Institute of Botany in Leningrad. The macromorphological characters of the sporophyte as well as the morphology and colour of spores were used. It has been found that Dryopteris extremiorientalis V. Vasil., regarded as an endemic taxon for the Far East, is conspecific with Dryopteris assimilis S. Walker, and Dryopteris Alexeenkoana Fom., regarded as a West Caucasian endemic species is identical with Dryopteris dilatata (Hoffm.) A. Gray, em. S. Walker. In .the paper the distribution of D. assimilis in the Asiatic part of the USSR was given.