THE FERN PARADISE. 
1 . 
THE TUNBRIDGE FILMY FERN. 
Hymenophyllum tunbridgense. 
Plate 8, Fig. 1. 
HE Tunbridge Filmy Fern— so called be- 
cause it was first noticed in the neigh- 
bourhood of Tunbridge Wells — is a tiny 
moss-like plant frequently found growing on rocks 
and boulders in the immediate vicinity of streams of 
water. The filmy, pellucid texture of the fronds 
would shrivel up, were the plant exposed to dry, hot 
air. It can only therefore exist in a constant atmos- 
phere of moisture, such as is to be found where 
water is continually present. It delights in the 
spray of waterfalls, or to be perched on the damp 
rocks round which the mountain streams rush and 
roar. In such situations it has a wide distribution 
throughout the United Kingdom. The fronds grow 
from little black, wire-like rhizomas, which often 
become densely interlaced with the mosses which 
grow on boulder-tops in mid-stream, or wherever 
perpetual moisture makes moss life predominant. 
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