THE BUCKLER FERNS. 
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abundant moisture and complete shade, and sandy 
peat and leaf-mould for soil. Then it may be 
grown successfully in the open rockery, in the 
fern case, or in open pots in the house. 
4. THE RIGID BUCKLER FERN. 
Lastrea rigida. 
This fern is local in its distribution ; very rare 
in Ireland, and not found at all in Scotland or 
Wales. But in some parts of the north of 
England, especially in the mountainous limestone 
districts, it is found in abundance. It appears to 
prefer a limestone soil : and in cultivation it is 
beneficial to water it with lime-water. When 
growing wild it is usually found from one to two 
feet high. Its fronds are somewhat narrow and 
triangular, with branches alternately placed on 
each side of the rachis. The branches are lance- 
shaped, having on each side, over and under the 
stem, a row of leaflets, largest next the rachis, and 
becoming shorter towards the point of the branch. 
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