20 
BRITISH FERNS. — SUB-ORDER II. TRIBE 3. 
farshire, and Glen Fiadh, Clova Mountains (the late Professor 
Balfour), on Ben Lawers (both by Mr. W. Wilson and Mr. Dickson), 
and between Glert Lochy and Glen Dochart (Mr. J. T. Syme). 
It is a native of Finland, Sweden, Lapland, Norway, Russia, 
Germany, France, Switzerland, Spain, Siberia, Silesia, Transylvania, 
Hungary, Rocky Mountains, on the Himalaya, and in Mas- 
sachusetts. 
There are no varieties. 
Tribe 3. H YMENOPH YLLE/E. 
THE ONE-SIDED FILM FERN. 
Hymenophyllum unilaterale.— Bory. 
(H. WlLSONI. — Hooker.) 
A moss-like fern which might readily 
be mistaken for one of the Musci family, 
having pellucid-membraneous fronds, 
from 1 to 6 inches in length. Pinnate, 
the pinnae divided into 5 or 4 lobes. 
Involucres stalked, the upper margin 
serrated. Growing in very damp situa- 
tions amongst moss on the ground or at 
the base of trees, and on wet rocks. 
Found in Cornwall, Devon, Stafford, 
Salop, Lancashire, York, Northumber- 
land, Westmoreland, and Cumberland 
(in the English lakes in at least a score localities), Glamorgan, 
Brecknock, Cardigan, Carmarthen, Montgomery, Merioneth, and 
Carnarvon. In 13 Scotch counties, 12 Irish counties, Mull, Arran, 
Shetland, Orkney, and Harris. 
A native of Norway, Faroe, Bourbon, New Zealand, Chiloe, 
Falkland, Tierra del Fuego, Cape Horn, Tasmania, Cape of Good 
Hope, and Hermite Island. 
The fronds endure for several years, and renew their growth 
annually. Mr. Gray of Alphington had a plant that had fronds 6 
inches long, many of which became branched by subsequent 
growths. 
Varieties.* 
*1 Kinahani, Lowe. Found in 1870 in the Galway Mountains 
by Mr. R. Kinahan, of the Irish Geological Survey. A long narrow 
form. 
2 Ramosum, Gray. Found in 1867 on Sheep’s Tor, Dartmoor, 
by Mr. R. J. Gray, and in 1882 on the Mourne Mountains, Ireland, 
by Mr. R. L. Praeger, length 4^ inches. Branching several times 
from the main stem. 
Fro. 3.— Hymenophyllum uni- 
laterale (showing fructification). 
* All varieties marked thus (*) have received 1st class Certificates from the 
Royal Horticultural Society or Royal Botanic Society. 
