FERNS AND MOSSES 121 
The Filmy Ferns above mentioned are very numerous. 
They are sometimes very minute, of a moss-like appearance, 
and are, when cultivated in a moist atmosphere, always covered 
with dew. They are among the most remarkable plants known, 
exceedingly beautiful, with fronds of almost hair-like appear- 
ance. ‘They must be grown in a glass-case or terrarium. 
Pteris argyrea. 
Club mosses are suitable for the same purpose as filmy ferns. 
Some are tender and creeping and form dense masses on the 
ground ; others are erect and of a robust habit. None are 
common in cultivation, but they deserve mention in connec- 
tion with the terrarium. All require a moist atmosphere and 
should be grown in rich vegetable, somewhat sandy soil. 
