CHARACTERS OF TRIBES AND GENERA. 261 



widely spread over the tropics of both hemispheres ; and 

 on account of the apparent or but slightly varied forms 

 being found in different countries, has led to great con- 

 fusion in the species. In the " Species Filicum," under 

 Davallia polypodioides, Sir William Hooker says : " The 

 more I study the Ferns, and compare specimens from 

 different countries, the more difficult I find it to define in a 

 specific character the essential distinguishing character of 

 species with the much divided fronds ; so different are 

 they, according to locality, to age on the various portions 

 of the same individual, and other circumstances. Then the 

 nature and degree of pubescence augment the difficulty ; 

 and all these difficulties seem to be combined in the pre- 

 sent species." Upon this view he unites about a dozen 

 specific names of authors under Davallia polypodioides of 

 Don, a species originally named and described by D. Don 

 on Nepal specimens. 



Sp. M. pinnata (Cav.) (D. flagellifera, Wall., Hook, and 

 Grev. Ic. FiL, t. 183); M. gracilis (Bl.) ; M. Moluccana 

 (Bl.)-, M. rhomboidea (Wall.) (Rook. Seed. Cent., t. 48); 

 M. scabra (Don.) (v v.) ; M. Khasyana (Hook.) ; M. cris- 

 tata (Hook.) (v v.) ; M. calvescens (Wall.) ; M. SpeluncaB 

 (Linn.) (D. polypodioides, Don., Hook. Sp. FiL, D. fiaccida, 

 R. Br.) (v v.) ; M. Novae-Zelandia3 (Col.) (v v.) (Acrophorus 

 hispidus, Moore) ; M. strigosa (Sw.) (v v.) ; M. hirta 

 (Kaulf.) ; M. trichosticha (Hook.) (vv.) ; M. alata (Hew.) 

 M. adiantoides (Sw.) ; M. platyphylla (Don.) (v v.) 



143. SCYPHOLEPIA, /. Sm. 

 Davallia sp., Wall., Hook. Sp. Fil. 



Vernation uniserial. Fronds contiguous, pinnate, 2 to 2 

 feet high ; pinnae lanceolate, 4 to 5 inches long, serrate, 



