162 
FERNS : BRITISH AND FOREIGN. 
§ 1. Woodsia vera. Stipes with a special articulation. 
Membrane ofindusium nearly obsolete, fringed with articulated 
hairs, which involve the sporangia. 
1. W. Ilvensis, R. Br.; Hook. Brit. Ferns, t. 8; Eng. Bot. 
i. 2616; Sowerby’s Ferns, t. 5; Hindi, and Moore's 
Brit. Ferns, t. 47 A. Acrostichum Ilvense, Linn. 
Polypodium Ilvense, Sw. ; Sclik. Fit. t. 19. — Europe, 
Britain. T. 
2. W. hyperborea, B. Br. in Trans. Linn. Soc. 11, t. 11 ; 
Hook. Gen. Fil. t. 119 ; Hook. Brit. Ferns, t. 7 ; 
Sowerby’s Ferns, t. 6. Polypodium hyperboreum, 
Sw. ; Eng. Bot. t. 2023; Schk. Fil. t. 17 B . — Europe, 
Britain. ' T. 
§ 2. Fhysematium. Stipes not articulated. Membrane of in~ 
dusium complete, at length somewhat sinuosc-laciniated. 
3. W. polystich.oid.es, Eaton; Hook. 2nd Cent. Ferns, t. 2. 
/3 Veitchii, Hook. Gard. Ferns, t. 32. Woodsia 
Veitchii, Hance, MSS . — Japan, Manchuria. 
4. W. obtusa, Hook.; Hook. Gard. Ferns, t. 43; Lowe’s 
Ferns, 7, t. 29. Polypodium obtusum, Sw. ; Schk. 
Fil. t. 21. Woodsia Perriniana, Hook, et Grev. Ic. Fil. 
t. 68. — North America. 
5. W. mollis, J. Sm. ; Lowe’s Ferns, 7, t. 26. Physematium 
molle, Kv.nze, Anal Ptcrid. t. 27. Woodsia Mexicana, 
B. Br . — Mexico. H. 
§ 4. Artliropterce. Fronds always pinnate ; pinnae entire 
or subpinnatifid, always articulated with the rachis. Sori 
pundiform, terminal. Indusium reniform, rarely obsolete or 
wanting. 
78 ARTHROPTERIS, /. Sm. 
Vernation uniserial, distant ; sarmentum slender, scandent; 
stipes pseudo-articulated ; the node of articulation basal 
or more or less elevated. Fronds pinnate, 1-1£ foot long ; 
