44. 
THE TUNBRIDGE FILMY FERN. 
Hyvienophyllum tunbridgense. 
Plate 6, Fig. 2, Page 235. 
Our native Filmy Ferns are the tiniest and most fragile- 
looking of the British species. They indeed occupy the sort 
of border-land which exists between the Ferns and the 
mosses. The common name of these Ferns very accurately 
represents their peculiar character, which is filmy and 
pellucid. The generic botanical name, Hymenophyllum, is 
compounded of two Greek words — hymen, a membrane, and 
ylny l Ion, a leaf, and refers to the membranous nature of the 
leafv expansion of the frond. If the leafy texture of the 
latter be examined with a magnifying-glass, it will be found 
to be beautifully reticulated, or its thin and almost tran- 
sparent substance to be woven of vegetable fibres like net- 
work. The specific name of the present species refers to 
the fact of its having been first noticed as a British Fern 
in the neighbourhood of Tunbridge Wells. It is mostly 
found growing on the damp surfaces of shady rocks, situated 
either along some watercourse or in damp woods. But not 
unfrequently it has been found clothing the trunks of trees 
in or near streams, or in very damp and sheltered situations, 
and occasionally even growing amidst moss on the ground. 
In such situations it is commonly found growing in company 
with mosses of various kinds, its hairlike rhizomas and root- 
lets being intermixed with the mossy roots. We have found 
