186 THE FERN PARADISE. 



the mossy covering of the wall, had crept along 

 until they formed a sheet nearly a foot square. 

 Then, the atmosphere of the brook had wonderfully 

 helped the vigorous growth of the plant. We took 

 our specimens from their damp and mossy habitat 

 carefully preserved them during our stay in Devon- 

 shire, by keeping them constantly moist and then 

 brought them to our London home. But we did 

 not forget to supply as nearly as possible the 

 conditions under which we found them growing 

 in their natural home. Shade, moisture, and leaf- 

 mould, are the three conditions of success for 

 the Common Polypody. It requires no great 

 depth of soil; but that soil must be leaf-mould. 

 We brought the leaf-mould from Devonshire with 

 our little stock of Polypodies. Some of these we 

 planted out in our rockery. All have succeeded 

 to perfection. But the grand plant before us 

 has exceeded our most sanguine expectations. 

 All we did was simply to strew the bottom of a 

 small seed-pan nine inches wide by three inches 

 deep with broken pieces of flower-pot ; upon that 

 to place leaf-mould, and plant our Polypody there- 



