Nephrolepis DAVALLIACEAE-PTERIDACEAE Hypolepis 



being usually kidney shaped.) 



Key to the Species 



Leaves 4 to 6 cm. broad ; apex of pinnae obtuse 1 . N. cordi folia 



Leaves 8 to 12 cm. broad; apex of pinnae acute 2. N. exaltata 



1. Nephrolepis cordifolia (L.) Presl Narrow Sword Fern (H. S. F. 300). 35-75 cm. 

 tall; fr. I— XII ; lower pinnae reduced to lobes. Asia, Australia, South America; 

 locally in Che., Ku. Cultivated. 



2. Nephrolepis exaltata (L.) Schott Broad Sword Fern (H. S. F. 301). 60-100 cm. 

 tall; fr. L-XII; lower pinnae slightly shortened. Asia, Polynesia, South America; 

 locally in Ku. Cultivated. Mutants are called Boston Fern. 



2. Davallia Smith Basket Fern #?$}§ M (Ku Sui Pu Shu; 

 Repair-fractured-bones Genus) 

 Petrophilous or epiphytic ferns: rhizomes thick, widely creeping, densely covered 

 with ciliate scales: leaves far apart, ovate to deltoid in outline, usually finely dissected: 

 sori at ends of veins, marginal or submarginal; indusium tubular or occasionally 

 cup-shaped, attached by sides as ivell as base, often coriaceous. 36 species. (Named 

 for Edmund Davall, 1763-1798, Swiss botanist.) 

 1. Davallia mariesii Moore Maries' Basket Fern #£ i J , H##ffl (Haichow Ku Sui Pu) 

 (DeV. F. 84). 12-25 cm. tall; fr. V-X; lamina deltoid, quadripinnatifid. China, 

 Japan, Korea; locally in Ku. Cultivated or on rocks. Fig. 13. 



3. Humata Cav. [iHHUM (Yin Shih Chiieh Shu; Shadystone Fern Genus) 

 Small petrophilous or epiphytic ferns: rhizomes densely scaly: leaves articulate 

 to the rhizome; lamina coriaceous, usually deltoid in outline, pinnate to tripinnate; 

 fertile leaves usually more dissected than the sterile: indusium coriaceous, reniform 

 or suborbicular, attached by broad base; sides free. 43 species. (Latin meaning "of 

 the earth"; since the rhizomes creep on the soil.) 

 1. Humata tyermannii Moore {Davallia tyermannii Moore) (H. S. F. 467). 10-25 cm. 

 tall; fr. V-XI; indusium ovate or suborbicular. China; locally in Che., Ki., Ku. 

 On rocks by streams. Fig. 14. 



17. PTERIDACEAE Gaudich. Wk (Chiieh K'o) 

 Mostly terrestrial ferns; some petrophilous; some decidedly xerophytic: rhizomes 

 long-creeping or short; some covered with hairs; some with scales: stipe not articulate 

 to rhizome: sori marginal, round or linear, borne on the apices of free or connected 

 veins; indusia distinct, confluent or continuous, formed by the more or less modified 

 reflexed leaf margin (in Pteridium the reflexed leaf margin covers an inner thin 

 indusium): veins free, or with the tips of veins connected at the margin: stipes glossy 

 in some genera. 27 genera. 



Key to the Genera 

 a. Indusia reaching nearly to the midrib: leaves decompound; ultimate 



segments small, elliptical 7. Onychium 



aa. Indusia not reaching to the midrib, 

 b. Sori clearly distinct. 



Rhizome and stipe hairy: sori borne on end of a single vein; 



indusia small, formed by reflexed marginal lobe 1. Hypolepis 



Rhizome and stipe scaly: sporangia borne upon and hidden 



beneath the reflexed marginal flaps 8. Adiantum 



34 



