THE POLYPODIES. 



The Limestone Polypody lias not a wide distri- 

 bution. It occurs in localities in the north of 

 England, and is found in some parts of the West 

 and in Wales. But from Scotland and Ireland 

 it is almost entirely absent. It is, however, not 

 an uncommon Fern in the limestone districts 

 where it grows. 



It is very much hardier in its constitution than 

 the Oak Fern, and will sometimes thrive well 

 when placed on the sunny or exposed part of a 

 rockery, or in the most sunny part of a green- 

 house. The soil which suits the other Polypodies 

 will suit Polypodium calcareum. But from its 

 fondness for limestone it will be supposed that the 

 presence of limestone in the soil is desirable. In 

 cultivation, therefore, small pieces of limestone 

 should be mixed with the soil in which it is 

 grown. Like all the Polypodies it has a creeping 

 rhizoma, which travels half under the surface of 

 the ground, its matted fibrous roots finding their 

 way into the lower depths of the soil in which it 

 grows, whilst from its upper surface grow the 

 clusters of dark bluish-green fronds. 



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