110 



POPULAR HISTORY OF LICHENS. 



be allowed to dry spontaneously, subsequently fastened to 

 pieces of cardboard, and arranged in shallow drawers, like 

 eggs or shells, — or they may be kept in small pasteboard 

 trays similarly arranged, or packed in thin paper, like mine- 

 rals. In the case of the Cladonias, also, the individual plants 

 may be detached, steeped in water, dried, and compressed, 

 like fruticulose and filamentous species. Many species ad- 

 here so intimately to, or are so incorporated with, their base 

 of support, that it is impossible to separate them, and it 

 then becomes necessary to remove with them a portion of 

 the latter : such are the Lecideas, Verrucarias, Graphideee, 

 and many Lecanoras. In the case of corticolous species a 

 portion of the bark must be removed by the knife, and 

 ought to be dressed on the spot into a neat and convenient 

 form. For saxicolous Lichens the geological hammer is 

 called to our aid, and the portion of the rock removed 

 should be dressed, and subsequently preserved, according to 

 the rules observed in the collection and conservation of mi- 

 neralogical and geological specimens. Corticolous and saxi- 

 colous species, which cannot be detached from their base of 

 support, are probably best arranged on cardboard in trays, 

 or packed in paper as above mentioned. In whatever way 

 arranged, it is advisable, so far as possible, to select speci- 



