IV. - WOODSIA. 
69 
HYPCTBOBEA, R. Brown : Engr. Bot. 2023 : Sm. Eng. 
Fl. iv. 3 1 : Hook and Arn. Fl. 567 : Franc. 27. W. ILVENSIS, van., 
Bab. Man. 409. W. ALPINA, Newm. 143 : Florigr. Bnt. iv. 46. 
ACROSTICHDM ALPINCM, Bolton. A. HYPEKBOREPM, Liljeblad. 
POI.YPODIUM HTPERBOBEUM, Swartz. P. AXVONICUM, Withering: 
Sm. Fl. Brit. 11 15. 
Two forms of this species are distinguished by Mr. 
Babington gracilis with linear-lanceolate fronds, tri- 
angular pinnatifid pinnae, cut into 
5-9 obtuse lobes, which are entire, 
or the lowest one crenate ( Wood- 
sia hyperborea, Eng. Bot. ; Poly- 
podium hyperboreum /3 gracile, 
Wahl.) ; and alpina having ob- 
long fronds, triangular oval pin- 
nae, with 3 5 rounded very 
blunt lobes ( W. alpina, Newm. ; 
Polypodium hyperboreum, 
Walil. ; Acrostichum, alpintim, 
Bolt). 
The Alpine "Woodsia has a 
thick tufted caudex, from which 
are protruded the blackish wiry 
roots. The fronds which die down 
annually, growing up again in 
spring, are narrow, almost linear, 
pinnate ; more tender and mem- 
branous than W. ilrense ; gla- 
brous, or nearly so, though some- 
times the stipes, rachis, and veins 
beneath bear some scattered hairs, 
mixed with a few pale chaffy 
scale. 1 ?, which are chiefly present 
hi the young state, and appar- 
ently very easily displaced. The 
stipes is articulated as in the 
last species, the lower part re- 
maining adherent to the tufted 
caudex. The pinnae are trian- [Woodsia alpina.] 
