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OJOOK OF 
pinnfe with the racliis ; in this species the receptacles have 
a serrated external margin. 
Hooker mentions the Filmy-fern in his ' ' FloraTLon- 
dinensis," as belonging to a very beautiful and extensive 
genus, established by Smith, for the most part inhabiting 
the tropics. One species alone is European, though not 
included in the Floras of Germany and Switzerland, 
notwithstanding their rocks and waterfalls, and damp, 
