2 ADIANTUM. 



GENUS I. 



ADIANTUM. Linnaeus. J. Smith. 



The fronds of the genus Adiantum have a curious property 

 of repelling moisture, hence its name, Adiantos meaning dry. 

 The form of the sori is reniform, oblong, round, or linear; 

 they are placed on the margin of the pinnae, either in a 

 continuous line or interrupted. The venules are direct, their 

 apices terminating in the axis of the indusium. The indusium 

 is venose, being formed of a reflexed crenule, of an oblong 

 linear or reniform shape, according as the margin of the frond 

 is crenulate, or more or less entire. The indusium on the 

 under side is sporangiferous, after a time becoming replicate. 



The midrib of the pinnae eccentric or wanting. 



The veins are unilateral or radiating, and are forked. 



The form of the frond is either simple, pinnate, pedate, 

 bipinnate, reniform, or decompound; varying in its length from 

 six inches to three feet. The fronds are mostly smooth. 



The stipes and rachis are mostly black in colour, and have 

 a polished glossy appearance. Usually the pinnse are oblique, 

 truncate, or wedge-shaped at the base, or dimidiate, and onlv 

 soriferous on the upper margin, mostly articulated with the 

 rachis or petiole. 



Sir William Hooker, in his splendid work, "Species Filicum," 

 has described no less than one hundred and eight species of 

 this lovely tribe of plants; many of them, however, are unknown 

 as cultivated plants. 



The majority of the Adiantums are natives of tropical or 

 temperate climates. 



