CHARACTERS OF TRIBES AND GENERA. 219 



the fronds being smooth, shiny, of a hard, dry texture, and 

 by the ultimate divisions being terminated by a spiny 

 point. The fronds of Lastrea, on the contrary, are soft, 

 and generally villose, and soon wither and crumple up 

 when separated from the plant. 



In arranging the species I have followed the plan indi- 

 cated in my "Catalogue of Cultivated Ferns," by which 

 they are thrown into two natural groups ; one with fasci- 

 culate vernation and lanceolate pinnate or bi-tripinnate 

 fronds, typically represented by P. aculeatum, and the 

 other with sarmentose vernation and generally distant, 

 bipinnate or decompound deltoid fronds, like P. coriaceum. 



Sect. 1. PolysticJium verum. 

 Vernation fasciculate, generally erect, acaulose. 

 * 



Type. Polypodium loncMtus, Linn. 



Sp. P. Plaschnickianum (Kunze) ; P. rhizophyllum 

 (Sw.) ; P. auriculatum (Sw.) ; P. mucronatum (Sw) (vv.) ; 

 P. falcinellum (Sw.) (v v.) ; P. acrostichoides (Sw.) (v v.) 

 (A. auriculatum, Sclik. Fil., t. 30) ; P. munitum (Kaulf.) ; 

 P. lepidocaulon (Hook.) (v v.) ; P. Lonchitis (Sw.) (v v.) ; 

 P.triangulum (Sw.) (v v.) ; P. obliquum (Don.) (v v.) ; P. 

 ilicifolium (Don.) ; P. tridens (Hook.) 



** Fronds bipinnate. 

 Type. Polypodium aculeatum, Linn. 



P. aculeatum (Sw.) (v v.) ; P. lobatum (Sw.) ; P. angu- 

 lare (Willd.) (v v.) 



INDIAN, MALAYAN, CHINESE, AND JAPANESE. 

 P. Thomsoni (Hook.) ; P. Lachnense (Hook) ; P. Pres- 

 cottianum (Wall.) ; P. lentum (Don.) ; P. discretum (Don.) ; 

 P. Tsus-Simense (Hook.) ; P. tripterum (Kunze) ; P. obtu- 



