54 MOUNTAIN BLADDER PERN. 



are numerous and circular, very conspicuous when 

 fully grown, and, though crowded, do not run into 

 masses. 



This rare species of fern occurs wild only in Great 

 Britain, although it is found in rough and stony 

 places in several parts of the continent of Europe, 

 and in America. 



It was first found by Mr. Wilson, on Ben Lawers, 

 in Forfarshire, in 1836; and has since been esta- 

 blished by other botanists as a truly British species, 

 though rarely to be found. 



Little can be said about the artificial treatment 

 of this fern, as it does not appear to have thriven 

 well where it has been tried. Its natural condition, 

 however, would suggest a very open medium for 

 the roots, which thread their way through dripping 

 rocks and constantly abundant though not stagnant 

 moisture.* 



* Mr. Newman suggests a small quantity of sphagnum and 

 charcoal to be mixed with the soil in which it is planted. 



