190 FILICES. 



The plant is subject to variation in the depth and form of the serra- 

 tures of the pinnae. These Kaulfuss describes as being pubescent be- 

 neath ; but we find, among a very full suite of specimens, very few to 

 which this character would apply, the majority being glabrous on both 

 sides, although furnished with minute tubercles on the surface. The 

 lower 6 or 7 pairs of opposite alternate venules are angularly anasto- 

 mosing. Sori seated on and near to the base of the anastomosing 

 venules, close to the costaeform vein. Indusium, like the surface of 

 the pinnae, either naked or hairy, orbicular in form, with a deep 

 sinus at the point of attachment. 



61. WOOD SI A, R. Br., Hook., J. Sm. 



(Physematium, Kaulf. Hymenocystis, C. A. Meyer. Polypodii Spec. Auct.) 



1. WOODSIA INCISA, Hook. & Grev. 



Woodsia incisa, Hook. & G-rev. Ic. Fil. t. 191; Hook. Spec. Fil. 1, p. 63, subgen. 

 Perrinia. 



Hab. Obrajillo, Andes of Peru. 



All our specimens of this, although considerably smaller, accord in 

 their essential characteristics with Hooker and Greville's figure and 

 description of the species. 



2. Woodsia Ilvensis, R. Br. 



Woodsia Ilvensis, R. Br. in Linn. Trans. 11, p. 173; Hook. Fl. Bor.-Amer. 2, p. 

 259; Hook. Spec. Fil. p. 63. 



Hab. Oregon; on the banks of the Columbia River, near Fort 

 Okonagan : in rocky places ; rare. 



Plant about 6 inches high, with from 20 to 30 fronds in a tuft. 

 Stipe, rhachis, costa, and veins crinite, and with a few large, pale- 

 brown, entire, chaffy scales at the base of the former. 



