THE SHIELD FERNS. 
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fern. The fronds are dark green in colour and 
rigid in texture. When the Hard Prickly Shield 
Fern has reached maturity in September, the 
backs of all its leaflets, in the upper portion of 
the frond, are densely covered with rich-brown 
clusters of seed-cases. 
The Hard Prickly Shield Fern is very widely 
and plentifully distributed throughout the United 
Kingdom, growing chiefly in shady hedge-banks 
and on tree-covered hilly slopes. Few of our ferns 
are so robust as this species, and few can bear 
the sunlight better. But, although hardy in the 
extreme, it prefers — like all ferns — shade and 
moisture, and grows more luxuriantly under 
conditions where these are secured than when 
exposed to the sunlight or subjected to the open 
force of the winds. We found a grand specimen 
of Polystichum aculeatum on a steep slope in 
the woods surrounding Berry Pomeroy Castle, in 
South Devon. It was nearly four feet long ; and 
its rigid, robust, prickly-looking, dark shining- 
green fronds made it a striking object. 
In the garden, on the rockery, or in the house, 
