THE SHIELD FERNS. 
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doubtless on account of the more evergreen, rigid 
and vigorous character of its fronds. Both ferns 
are beautiful ; but there is a soft beauty and 
a gracefulness of aspect about the Soft Prickly 
Shield Fern scarcely possessed in the same 
degree by its more robust relative, Aculeatum. 
3. THE HOLLY FERN. 
Polystichum lonchitis. 
Differing in many essential points from the 
other species of Polystichum , the Holly Fern has, 
nevertheless, a clearly defined relationship to 
Aculeatum and Angulare. It is, indeed, a singular- 
looking yet withal a beautiful fern ; and its 
leaflets possess a sufficiently near resemblance 
to the leaves of a holly-bush to warrant the 
name which it bears. Sometimes this fern grows 
to a height of only six inches or so. At other 
times it may be found exceedingly vigorous, grow- 
ing as long as eighteen inches, and under such cir- 
cumstances very stiff and erect in habit. It is a 
