150 FERNS IN THEIR HOMES AND OURS. 



investigation by microscopists, who use their sili- 

 cious cases as test-objects for high-power objec- 

 tives. 



The parallel group of Fungi is generally very 

 uninteresting as presenting objects for collection, 

 although much investigated by patient scientists. 

 Many species among the larger ones are edible ; 

 and the mushroom {Agancus campestris) is fre- 

 quently seen at horticultural exhibitions, though 

 it is seldom that this excellent vegetable reaches 

 the suburban markets. Old specimens of Polypo- 

 nis, the shelf-like, woody fungus which grows 

 upon old trees, may be easily converted into a 

 bracket upon which to place a pot-plant or a vase. 



The Lichens are very tempting to collectors, 

 in the hope that they may be made to flourish in 

 the fernery; but they soon mould, and spread 

 trouble among the ferns. One of the most beau- 

 tiful, the EvcTuia vulpina of California, is a fine 

 object to use for house decoration in company 

 with the Tillaiidsia, and, like most of the pendent 

 Lichens^ may be washed when dusty. 



Of the CharacecB many species may be found 

 in ponds and rivers, sometimes growing in quite 

 deep, but more frequently in shallow water. Some 

 have a very unpleasant smell, resembling sulphu- 

 retted hydrogen, when first collected ; and some are 

 covered by a deposit of carbonate or phosphate 

 of lime, which is secreted by the plant, and hence 



