POLYSTICHDM ANGULARE. 239 
|/ POLY'STICHUM ANGULA'RE. 
THIS is the Aspidium aculeatum of the botanist Kunze. 
Indeed, there is much disagreement among authorities 
as to the differences between Polystichum aculeatum and 
P. angulare and their varieties. As there are sufficient 
points of distinction we have avoided, by retaining them 
as separate species, any attempt to reconcile the dissen- 
tients. That now under our consideration is the Aspi- 
dium angulare of some botanists. In English it has 
been called Angular-leaved Shield Fern, Soft Prickly 
Shield Fern, and Angular Prickly Shield Fern. 
Its main root is large, tufted, often upright and trunk- 
like when old. It sends forth many creeping side-shoots, 
which produce crowns, and the whole are furnished with 
many coarse, wiry rootlets. The fronds spear -head 
shaped in general outline vary in height from two to 
four, and even more, feet. They are more soft and deli- 
cate in their texture than those of P. aculeatum, con- 
sequently they are more flexible, drooping, and elegant 
in their habit of growth ; they are also more shaggy. 
Of the stem about one-fourth is unleafleted, and is, as 
well as the stalks of the leaflets, very thickly covered 
with reddish-brown chaff-like scales. Towards the ex 
treme ends of the leaflets the scales gradually are finer 
until they really become hairs. The leaflets are alternate 
and narrow spear-head in outline. The lea/its are alter- 
nate, flat, stalked, and would be pointed egg-shaped if 
the upper side did not produce near its base an irregular- 
