20 HYMENOPHYLLUM UNILATERALE. 



More widely spread throughout England, Scotland, Ireland, 

 and Wales, than H. Tunhridgense. 



Native also of Norway, the Faroe Isles, Bourbon, South 

 Africa, Terra del Fuego, Cape Horn, Falkland Isles, Tasmania, 

 and New Zealand. 



Fronds smooth, pellucid, membranaceous, dark green in colour, 

 elongate-oblong, and pinnate. Pinnae decurrent in the upper 

 part, distinct below, curved backwards, and digitately pinnatifid. 

 Segments linear obtuse, and spinulosely serrate. 



Veins dichotomously branched. 



Sori extra marginal. Involucres turned in an opposite direc- 

 tion to that of the segments. 



Valves ovate-oblong and convex, the edge entire. 



Phizoma rigid, creeping, branched, filiform, and dark brown. 



Stipes slender and wiry; rachis narrowly winged above. 



Length of frond from two to six inches. 



Mr. Clowes remarks that the fronds resume their growth for 

 several years, and that this is not the case with H. Tunhridgense. 



Mr. Gray, of St. Thomas', Exeter, has forwarded to me plants 

 of a branched variety, which is here figured as variety Ramosum, 

 (see Plate VI. — B.) It is very handsome, the divisions being 

 narrower, and the plant altogether more slender. This species 

 has a tendency to become branched. 



My thanks are due to Mr. P. J. Gray, St. Thomas', Exeter; 

 Miss Millett, of Penzance; Mrs. Delves, of Tunbridge Wells; 

 and Mr. Clarke, gardener to W. Dent, Esq., Crosby Pavensworth, 

 for plants of this species. 



It may be procured of any Nurseryman. 



The illustrations are from plants forwarded by Mr. Gray. 



