Cystopteris Cystopteris, R. Sim

2. C. dickieana R. Sim View in CoL , Gard. Farm. Jour. 2 (20): 308 (1848).

Like 1 but with rugose spores. 2/7= 168. Probably occurring sporadically throughout the range of 1. Br Fe Ga Ge He Hs Is No Rs (N) Sb Si Su.

Originally described from Britain, where the plants represent a variant in which the pinnae are deflexed and horizontally overlapping and inclined, and the pinnules wide, obtuse, more or less overlapping, crenate to crenately lobed. C. baenitzii Dörfler in Baenitz, Herb. Eur. Prosp. 1891: 4 (1890), is a Scandinavian variant which is more like 1.

1 and 2 form a widespread, polymorphic, polyploid complex in which it is difficult to classify the variation. Tetraploid and hexaploid populations of 1 cannot as yet be distinguished with certainty either from one another or from diploid populations which have been recorded from North America. Sterile hybrids between 1 and 2 are known.