WILLD enow’s fern. 
173 
t WILLDENOW’S FERN [one-twentieth the natural size). 
PoLYSTiCHUM ANGULARE, Newman. 
Aspidium angulare^ Smith, Hooker. 
This fern, like the preceding, is almost universally distribut- 
ed : it is, however, confined much more exclusively to lowland 
regions, warm sheltered woods and hedge-rows, and seldom as- 
cends to any considerable altitude. In some parts of Ireland it 
is exeeedingly abundant, and seems to take the place of P. acu- 
leatum, which I consider the commoner fern in most parts of 
England. 
Without the means of comparing specimens, I presume, from 
the description which I have quoted below,* that the plant now 
under consideration is the Aspidium angulare of Willdenow. 
The roots and rhizoma present no characters by which I can 
distinguish them from those of the preceding. The stem is dis- 
tinct, about one fourth as long as the frond, and densely clothed 
* Aspidium angulare. “ A frondibus bipinnatis pitinulis oblongis subfalca- 
tis mucronato-serratis sursum auriculatis, infima elongata subpinnatifida stipite 
rachibusque paleaceis. W. 
“ Stipes tri- vel quadripollicaris paleaceus. Racbis universalis atque par- 
tialis paleacea sed paleae tenuiores. Frondes sesqui- vel bipedales bipinnatae. 
Pinnae tripollicares et longiores. Pinnulae oblongo-subfaleatae acutae basi cune- 
atae, sursum acute auriculatae serratae serraturis mucronatis. Pinna infima su- 
perior reliquis longior pinnatifido-serrata. Sori subrotundi. Affine A. aculeato 
sed praeter formam pinnularum praecipue pinnula infima pinna bifida et habitu 
laxiore diversum. W.”“Willd. Sp. PI. 257. 91. 
