ADIANTUM. 



299 



what irregular in form, the lower ones being 3in. to 4in. long and 2in. 

 broad, so large at the base that the opposite ones frequently overlap : some- 

 times their margin is deeply dented, at other times their edges are nearly 



Fig. 42. Adiantum macrophyllum 

 (h nat. size). 



smooth, both forms being generally found on the same plant. The fertile 

 pinnas, of the same shape, are narrower than the barren ones, and the sori 

 (spore masses) are disposed in continuous or slightly interrupted marginal 



