OAK FERN. 



velopment, the fronds never assume the appearance 

 of the three little balls, as in Dryopteris. It is of a 

 darker duller green ; its stalk is more scaly at the 

 lower part green instead of purple, and the clusters 

 of sori more densely crowded. It is found commonly 

 in Derbyshire, near Matlock, and abundantly in Cum- 

 berland, Westmoreland, Yorkshire, and Lancashire. 

 It does not seem to have been found in Scotland or 

 Ireland. 



The mealy dust which characterizes this fern is a 

 beautiful object under the microscope, each slender 

 stem supporting a globular head ; but as this appear- 

 ance soon goes off when the specimen dries, it is best 

 to examine freshly-gathered plants. 



There seems to be no great difficulty in cultivating 

 this fern in the ordinary soil of gardens, although it 

 does not thrive so well as some others in the atmo- 

 sphere of towns. When grown in the greenhouse, 

 it should be planted in large pans, with a free admix- 

 ture of limestone and crumbled and sifted mortar ; 

 full exposure to the sun has rather a beneficial effect 

 on it than otherwise. 



