This rare fern I was photographing on Saturday. They are very small (only about 5cm long) look more like a liverwort and are only found in one small area of woodland amongst boulders in the whole of the east of Northern Ireland. There are a couple of sites in County Fermanagh in the south west. I have been tracking this colony down for many months and literally stumbled upon it last week when I was just about to give up - there's a lot of woodland and a lot of large boulders to check! I reckon they are beautiful little plants and worth the search.
The leaves are translusent being only one cell thick.
Unfortunately my Sigma macro lens got damaged yesterday :-( so busy getting it packed up for repair - bad timing!