Hyaienoph yll um. 
17 
frond; each segment is short and pinnatifid, and spreads vertically; the alternate segments 
are narrow, obtuse, and distantly but conspicuously serrate. No stomata occur on the fronds 
of this or the other species. The fructification is usually produced in the upper half of the 
frond, the sori, which have two nearly round short compressed valves or segments conspicuously 
serrate on their upper margin (indusium), being borne usually at the apex of the first vein on 
the upper side at the base of each pinna. The fronds are all annual, and more elegant than 
those of II. unilaterale. 
The Tunbridge Fern likes shade, warmth, and shelter; it may be grown readily under a 
bell glass, especially if two small apertures be provided towards the top. It occurs naturally 
on moist rocks or old tree-trunks amongst mosses, which it much resembles ; when growing on 
the perpendicular surfaces of shaded rocks, the fronds are often nearly pendulous, which is 
also the case with the next species. 
H. tunbridgense , as understood by English authors, is a fern of limited range, occurring in 
Britain, France, Belgium, the Pyrenees, Saxony, the Tyrol, Italy, and Corsica ; but the authors 
of the “Synopsis Filicum” include under the same name several 
plants which have been regarded as distinct by various authors, 
and the range is thus extended to South Africa, Mauritius, 
Madeira, the Azores, the Auckland Islands, New South Wales, 
Jamaica, Venezuela, Chili, and New Zealand, and this without 
including II. Wi/soni, which is regarded in the “ Synopsis ” as a 
variety of H. tunbridgense. In Britain it occurs, or has occurred, 
in the counties of Cornwall, Devon, Somerset, Sussex, Kent, 
Glamorgan, Merioneth, Westmoreland, Cumberland, Northumber- 
land, Dumfries, Renfrew, Peebles, Stirling, Argyle, and Dumbarton, 
finding its north limit in Mull and the islands of the Clyde, and 
ascending to twelve hundred feet. In Ireland it is abundant in 
some of the western districts, especially in Kerry and Cork, but 
rare in the east centre and north of the island. From the greater 
part of central Europe, and all the north and east of the Continent 
and Asia, it is quite absent. 
The name tunbridgense commemorates the original discovery 
of the species near Tunbridge Wells, in Kent, some years before 1682, in which latter year 
it was found by Ray in Westmoreland : it is not now to be found in the neighbourhood of 
T unbridge. 
HYMENOPIIYLLUM WILSONI, Hook. 
This has a general resemblance in appearance and habit to the last species, with which it 
was for a long time confounded : the two are certainly nearly allied, but there are differences 
between them which a practised eye can readily detect, and which seem sufficiently constant, at 
any rate so far as British plants are concerned. II. Wilsoni is a larger and less elegant plant than 
H. tunbridgense, and is also more rigid and more coarsely reticulated. The fronds are not annual, 
but grow on year after year for several seasons, reaching, it is stated, as much as ten inches in 
length, though this must be of rare occurrence, but about six inches is a not unfrequent size. 
They differ in colour from those of H. tunbridgense, being of a darker green ; Mr. Wilson describes 
the hue of the last-named species as “glossy green.’’ The pinnae have a strongly recurved 
habit. The sporangia, which are more or less stalked, are usually solitary on each pinna, but 
5 
HYMENOPHYLI.UM 
TUNBRIDGENSE. 
