Wayside, Seaside, and Rock Ferns 



by a rounded notch. Unlike all other British ferns, the 

 Ceterach Fern has the back of its fronds so completely 

 covered with reddish-brown scales that we have a 

 difficulty in making out the sori. If, however, the 

 scales, which, it should be noted, are silvery white when 

 the fronds are first unrolled, be carefully removed, its 

 linear sori will be apparent. Indusia do not seem to 

 have been developed, the reason being that their work 

 of protecting the sori is performed by the covering 

 scales. But it is most probable that the chief function 

 of the scales is to act as a check on the transpiration of 

 water through the leaves, so that in addition to its 

 small leathery leaf segments, this fern has a further 

 means of defence against drought. 



If we were to visit this fern after a long spell of dry 

 weather, we should be inclined to say, judging from its 

 shrivelled up appearance, that it was in a dead or dying 

 condition. The segments of the fronds have folded 

 themselves together facing the midrib of the frond, 

 while the whole frond appears to be rolling itself up 

 from the tip downwards. But after a refreshing 

 shower of rain the fronds will again assume their fully- 

 expanded upright form. 



Of all ferns of the genus Asplenlum the Scale or 

 Ceterach was regarded as the most efficacious in curing 

 disorders of the spleen. In fact, according to the 

 legend, Cretan sheep, which greedily devoured the root- 

 stock, not only recovered from diseases of the spleen, 

 but in course of time lost that organ altogether. 

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