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GROUP I; GENUS IX. 
HYMENOPHYLLUM. 
Sori. Marginal. Some of the veins project beyond the 
margin of the frond, and on these projections 
the thecas grow, enclosed in two-valved in¬ 
volucres. These are situated near the junc¬ 
tion of the pinnae with the rachis. 
Veins. Free, and very strongly marked. 
GROUP I; GENUS IX; SPECIES I. 
HYMENOPHYLLUM TUNBRIDGENSE. 
(Tunbridge Film Fern.) 
Plate VII. 
Fronds. Lanceolate, pinnate, membranous and semi¬ 
transparent. Pinnae very deeply pinnatifid, 
and connected with each other by a pellucid 
wing extending along the rachis. Lobes ob¬ 
long and furnished with spines. Involucres 
globular, and flattened on the upper edge 
where they are fringed with spines. 
