258 CHARACTERS OF TRIBES AND GENERA. 



and is represented in New Grenada, Venezuela, Brazil, 

 and Jamaica by B. coniifoUum, which I consider to be 

 scarcely distinct from the preceding. 



Sp. B. Culcita (L'Herit) (v v.) ; B. coniifolium (Hook.) 



140. CYSTODIUM, /. 8m. (1841). 

 Dicksonia, Sm., Hook. Sp. Fil. 



Vernation fasciculate, erect, sub-arboroid ? Fronds stipate, 

 bipinnate, 2 to 3 feet long ; pinnse distant, 1 foot long, 

 pinnules linear lanceolate, acuminate, dentate, sub-auricu- 

 lated, truncate at the base, articulate with the rachis. Veins 

 simple or forked, parallel, their apices free, terminating in 

 the marginal dents, and sporangiferous ; accessory indusium 

 concave, vaulted and conniving with the smaller, plane 

 special indusium, the two together forming an unequal, 

 bivalved cyst, forming a row of marginal denteform sori. 



Type. Dicksonia sorbifolia, 8m. 



Illust. Hook, and Bauer Gen. Fil., t. 96. 



OBS. This genus is founded on a very rare Fern, first 

 described by Sir J. E. Smith in Ree's Cyclopaedia, from 

 specimens collected in the Island of Honimoe, Moluccas, by 

 Christopher Smith, between seventy and eighty years ago. 

 It appears not to have been since collected, as only three or 

 four specimens are to be found in herbaria in this country, 

 and these consist of portions of fronds only, and nothing is 

 known as to whether it has acaulose or arboroid vernation. 

 The marginal bivalved indusia agrees with some DicJcsonia 

 such as Cibotium, but its simple lanceolate pinnae being 

 articulate with the rachis, seems to indicate its relationship 

 to be with the section Arthropterece of Aspidece rather than 

 with any genus of Dicksonia, but till more is known of it, 

 I place here. 



Sp. C. sorbifolium (Swz.) (Hook. Sp. Fil., 1. t. 25 A) 



