146 THE MORPHOLOGY OF PTERIDOPHYTES 



Pflanzenfamilien^^). However, even when thus restricted, it 

 is still by far the largest group of the pteridophytes, for it 

 contains almost 300 genera and about 9,000 species. Details 

 of their form and anatomy would occupy many volumes 

 and can only briefly be summarized here, the following 

 famihes, subfamiUes and genera having been selected to 

 illustrate the salient points (the classification is based on that 

 of Holttum^^). 



Schizaeaceae Sehftenbergia* , Klukia*, Schizaea, Lygodium, 



Mohria, Anemia 

 Gleicheniaceae Oligocarpia* , Gleichenites*, Gleichenia 

 Hymenophyllaceae Hymenophyllum, Trichomanes 

 Dicksoniaceae Coniopteris*, Dicksonia, Cibotium 

 Matoniaceae Matonidium*, Matonia 

 Dipteridaceae Clathropteris* , Dictyophyllum*, 



Camptopteris* , Matonia, Phanerosorus 

 Cyatheaceae Alsophilites*, Alsophila, Hemitelia, Cyathea 

 Dennstaedtiaceae 



Dennstaedtioideae Dennstaedtia, Microplegia 



Pteridoideae Pteridium, Pteris, Acrostichum (?) 



DavalUoideae Davallia 



Oleandroideae Nephrolepis 



Onocleoideae (?) Onoclea, Matteuccia 



Blechnoideae Blechnum, Woodwardia 



Asplenioideae Asplenium, Phyllitis 



Athyrioideae Athyrium 



Dryopteridoideae Dryopteris, Polystichufn 



Lomariopsidoideae Elaphoglossum 



Adiantaceae Adiantum, Cheilanthes, Pellaea, 



Ceratopteris, Anogramma 



Polypodiaceae Platy cerium, Polypodium, Stenochlaena(J) 



As might be expected in such a large group, there is a 

 considerable range of form and growth habit, from tiny 

 annuals to tall tree-ferns and from protosteUc forms to those 



