POLYPODIACEiE. 277 



2. Dicksonia Sellowiana, Hook. 



Dicksonia Sellowiana, Hook. Spec. Fil. 1, p. 67, t. 22, B. 

 Hab. Organ Mountains, Brazil. 



In character this agrees precisely with the description and the 

 small figure in Hooker's Species Filicum. When the fronds are 

 young, the rhachis of the pinnules is furnished with articulated and 

 somewhat appressed hairs, which disappear with age. 



3. Dicksonia Berteroana, Hook. 



Dicksonia (Balantiwm) Berteroana, Hook. Spec. Fil. 1, p. 67, t. 23, A. 



Hab. Ovolau, Feejee Islands : at the altitude of 2,000 feet. 



Arborescent. Trunk 4 to 6 feet high, bearing large, spreading, 

 tripinnate, coriaceous, glabrous fronds, with a very thick and slightly 

 woolly stipe and main rhachis. Pinnules oblong-lanceolate, acumi- 

 nate, deeply pinnatifid, the point entire and serrate, of a paler colour 

 on the under than the upper surface, somewhat imbricated. Segments 

 oblong-ovate, subacute, serrated, somewhat falcate, the inferior one 

 often with a lobe at the base : rhachis of the primary and secondary 

 divisions clothed with a close fulvous tomentum above. Fertile 

 fronds smaller, cmadripinnate, the ultimate divisions parted down to 

 the costa into 6 or 8 lobes; or, in other words, the foliaceous sub- 

 stance of the frond is so contracted, that little more than the mere 

 costa and veins are present, these being at most slightly winged; each 

 lobe terminated by a single large sorus. The accessory indusium is 

 more concave, and larger than the special one. 



With the exception of the following species, this is perhaps the 

 most elegant of the genus. The fronds are not always strictly of two 

 kinds, for sometimes we find at the base of a generally sterile frond, 

 one or two contracted and fertile pinnules ; and, on the other hand, 

 what would be considered a fertile frond, frequently bears sterile 

 pinnules at the middle of the pinnae or elsewhere. 



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