164 



FILICES. FERNS. 



Members of this well known family are found in almost all parts 

 of the world, several species indeed have been found to inhabit the 

 polar regions, while in temperate countries they are more plentiful, 

 and in favoural)le situations of tropical countries they abound, 

 especially in tropical or subtropical islands, where the humidity of the 

 atmosphere is especially suitable to their growth. In size the planis 

 range from the minute species of Hymenophyllum and Trichomanes 

 with scarcely any stems, and fronds less than one inch long, and which 

 are frequently mistaken for mosses, to the large tree ferns with stems 

 •40 feet high, and fronds 10 to 15 feet long. The rhizomes of some of 

 the species are used medicinally as anthelmintics or astringents, the 

 fronds of others are mucilaginous, as are the young shoots also of 

 some of the species ; some of the species are strongly scented, includ- 

 ing' our indigenous Folypodium phymatodes and Nephrodium alho- 

 punctatuiH, and perhaps some others also. The scales or hairs which 

 are found i)lentifidly on some of the species have been used as styptics, 

 and also for stuffing pillows, cushions, iScc. Tljey are, however, best 

 known as ornamental plants, and a large number of species and 

 varieties are in cultivation. 



KEY TO SUBORDERS. 



Sori dorsal, of few (2 to lO) capsules. Capsules 

 opening vertically surrounded by a broad, 

 transverse complete ring, which opens ver- 

 tically by the separation of the joints of 

 the ring. Fronds dichotomously branching. 



Sori tenninal or marginal from the apex of a vein. 

 Receptacle elongated. Capsule roundish or 

 flattened, with a complete transverse ring 

 opening vertically. Involucre inferior, of 

 the same texture as the frond. 



Sori dorsal or marginal, subglobose, Avith oi- with- 

 out involucre, usually stalked, more or less 

 completely surrounded by a jointed elastic 

 ring, opening transversely. 



Capsules i^-valved, opening across the apex, and 

 furnished with a short horizontal ring. 



I'apsules :^-valved, opening at the side, and 

 crowned by a complete operculiform ring. 



Capsules concrete in a double line on the back of 

 the ordinary pinnai, opening by slits down 

 their inner faces. 



Capsules 'J-valved, without a ring, in two rows on 

 a linear frond. 



A. GLEICHENlACEiE. 



B. Hymenophylle^. 



C. PoLYPODIACEJi 

 O. OsMUNDACEi:. 



E. SCHIZ.^ACE.E. 



F. ALarattiace;!!;. 



G. OPfllOGIiOSSAC&E. 



