POLTPODIUM DRYOPTERIS. 17 



Sori scattered over the whole frond; situated below the 

 apices of the basal venules, circular, abundant, but minute. 

 Spore-cases small, deep brown in colour; spores ovate. 



Xo permanent varieties have been found of this handsome 

 Fern, which is singularly constant to its normal form. 



In its wild state the Oak Fern is quite a feature in the 

 landscape, and when travelling amongst the mountains in hot 

 summer days, there is a delicious coolness in the colour of 

 the fronds that is refreshing to the pedestrian, and makes him 

 remember with pleasure the Oak Fern — his mountain friend. 



