CHARACTERS OF TRIBES AND GENERA. 97 



** Fronds pinnate. 

 C. decurrens (Eadd.} (v v.) ; C. Fendleri, Eaton. 



14. NIPHOBOLUS, Kaulf (1824). 

 Polypodium sp., auct. ; Hook. Sp. Fit. 



Surculum short or elongating. Fronds csespitose or dis- 

 tant, simple linear-lanceolate, oblong elliptical or obovate- 

 subrotund, rarely lobed, from less than an inch to two or 

 three feet long, thick and fleshy or coriaceous, covered with 

 sessile or stipate, white or brown stellate pubescence ; 

 the fertile usually more or less contracted and longer than 

 the sterile. Veins obscure, undefined, or evident and 

 costseform ; venules compound anastomosing. Receptacles 

 punctiform, immersed, terminal or medial, on simple or 

 brachiate free veinlets, or compital. Sori round or oval 

 sub-transverse multiserial or biserial between the primary 

 veins, or irregular and confluent, protruding through the 

 dense stellate pubescense. 



Type. Polypodium adnescens Sw. 



Illust. Hook, and Bauer, Gen. Fil. t. 83 ; Hook., Ex, Fil. 

 t. 162 ; Moore, Ind. Fil. p. 61 ; J. Sin., Ferns, Brit, 

 and For. fig. 26 ; Hook, Syn. Fil. fig. 48. k. 



OBS. This genus is readily known by the thick coria- 

 ceous fronds being covered with stellate pubescence, which 

 gives them a hoary appearance when young ; in some 

 species this pubescence nearly disappears in age, especially 

 on the upper side of the frond. 



About forty species have been named and described by 

 different authors, but a critical examination has led me to 

 believe that not more than one-half of that number are 

 distinct species. In the " Species Filicum," the number 

 is reduced to twenty-two, which I believe might be still 

 H 



