"The publication of this series of papers on the nomenclature of the genera of pteridophytes was begun fifteen years ago under the general title of "Names ad types of fern genera". The first and second parts were issued in 1955 and 1957. This paper which deals with the living fern-allies belongs essentially to the same series." (p. 192)

Reprinted from Webbia, v. 26, no. 1, 1971, p. 129-194.

Includes index.

Summary in Italian.