94 
BRITISH FERNS . 
BRAKES OR BRACKEN—EAGLE FERN. 
PTERIS AQ U.ILIN.A, 
Linnaeus, Smith, Hooker and Arnott, Babington, Bentham, and 
Moore. 
(Plate XV. Fig. I.) 
SYNONYM. 
Eupteris aquilina , Newman. 
A WELL-KNOWN and very common species of fern, 
not at all difficult to recognise, by its large and strong 
growth, and the continuous lines of marginal sori on 
the compound bipinnate fronds. They are sometimes 
ten or twelve feet in height, and their texture is crisp 
and brittle. Each frond appears singly, and the 
growth of the plant is the reverse of being tufted. 
The root attains a very large size in a favourable 
soil, and Mr. Newman says he has found them buried 
as low as fifteen feet. The plant spreads very rapidly, 
and in some places acres of land are covered by it. 
The fronds turn brown at the first approach of frost, 
and decay away in the winter. The stem being hard 
and tough, and deeply buried in the earth, is not 
easily rooted up; but when cut across, presents on 
the two divided surfaces the figure of an Oak Tree, 
or as some fancy, a Spread Eagle ; hence its specific 
name. 
Although one of our commonest ferns, this plant is 
not luxuriant on chalky soil, but in sandy and stony 
districts it is most abundant, and by its handsome 
