THE OTHER BRITISH FERNS— POLTSTICHUM, ATHYRIUM, CETERACH 



these two species. Attempts to synthesize it have, however, been curiously unsatis- 

 factory. Only one author is known to me to have succeeded in carrying out a cross 

 between A. septentrionale and another species of Asplenium, namely Heilbronn (1910), 

 but even he was forced to point out a dissimilarity between the hybrid he produced and 

 the natural one.* It is true that a surprisingly contradictory statement was made by a 

 distinguished amateur, P. Kestner, who remarks in the British Fern Gazette of 1935 that 

 A. germanicum is the only fern hybrid that can be synthesized with ease. This statement, 



Fig. 98. The Welsh plant of Asplenium germanicum auct. non Weiss in its original habitat. Natural size. 

 From a photograph kindly supplied by the finder, Dr H. F. Dovaston. 



though perhaps true as will be seen below, cannot unfortunately be used as evidence, 

 since Kestner failed to authenticate it by keeping a record, photographic or otherwise, 

 of the plants he refers to. 



I am fortunate in having had access to living specimens of A. germanicum from several 

 different countries. A British specimen from south Wales, a leaf of which is shown in 

 Fig. 97a, was made available to me by the finder, Dr Dovaston, whose photograph of 

 it in its original habitat is also reproduced (Fig. 98). Two continental specimens were 



* Heilbronn claims to have crossed A. septentrionale with A. ruta-muraria. This should have yielded 

 A. Murbeckii Dorfl. and it is therefore not quite clear why the author was looking for A. germanicum, 

 although his photograph does show some points of resemblance to A. germanicum. 



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