29G 



F I L I C E S. 



with their points truncate or eraarginate, the slight pubescence 

 beneath of a lighter colour. Sir William Hooker refers this to the 

 M. pitbescens of Willdenow ; but we view the two plants, as truly 

 distinct species. 



10. Mertensia pubescens, Willd. 



Mertensia pubescens, Willd. Spec. PI. 5, p. 73. 

 Gleichenia pubescens, Hook. Spec. Fil. 1, p. 8, pro parte. 



Hab. Organ Mountains, Brazil. 



We consider this as distinct from the preceding species, on account 

 of its narrower branches, the inferior ones more spreading; the 

 shorter and less horizontal segments beset underneath with a dense 

 and rusty coating of a cobwebby substance ; and, moreover, the paleae 

 on the stipe and rhachis are of a more membranaceous or scarious 

 texture. The M. immersa of Kaulfuss, as figured in Hooker and 

 Greville's Icones Filicum, somewhat represents our plant; but it has 

 broader and more lanceolate branches. 



* * * Stipes dichotomies, divisionibus nudis Jiexuosis ; pinnis unijugis. 



11. Mertensia glaucescens, Willd. 



Mertensia glaucescens, Willd. Spec. PI. 5, p. 72. 



M. emargiuata, Rtddi, Plant. Brasil. 1, p. 72, t. 6. 



M. BrasiUana, Gaud. Bot. Freyc. Voy. p. 301. 



Gleichenia Bermanni, Hook. & Grev. Ic. FIL t. 14, excl. syn. 



G. glaucescens, Hook. Spec. Fil. 1, p. 11. 



Hab. Organ Mountains, Brazil. 



The glaucous surface of the pinnae underneath is partially con- 

 cealed by a ferrugineous and cobwebby down: the points of the 

 segments are almost always emarginate. Sporangia from 8 to 10 in 

 a cluster. 



