CHAPTER XII. 
THE FILMY FERNS. 
Plate 8. 
E Filmy Ferns form a sort of connect- 
ing link between Ferns and mosses. 
They are the tiniest of all the British 
Ferns, forming little tufts sometimes 
only one inch in length ; but sometimes growing 
to a length of six inches. Their semi-pellucid and 
filmy nature is sufficiently expressed in the common 
name given to them. The British group of these 
pretty little Ferns is a tiny one, including only two 
species, namely; — 1. The Tunbridge Filmy Fern 
( Hymenojohyllum tunbridgense), and 2. The One- 
sided Filmy Fern ( Hymenojohyllum unilaterale). 
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