INTRODUCTION, 



3 



and examined even by the humblest observer. The lichen- 

 ological student requires no cumbrous or expensive ap- 

 paratus : an old knife and hammer, a few pill-boxes or a 

 tin-case for collecting, a supply of cardboard and paper, 

 with gum or glue for preserving, and a pocket-lens and 

 microscope for examining, constitute his whole armamen- 

 taria. Nor is it necessary, for the purpose of collecting, to 

 run the risks or suffer the expense of foreign travel : the 

 objects of his search surround him abundantly ; from the 

 sea-coast to the mountain summit, he will find them on 

 every tree or rock. Moreover they may be collected at all 

 seasons, in all weathers and climates, at almost all eleva- 

 tions, and in all countries hitherto discovered. But their 

 very familiarity — the very simplicity and inexpensive nature 

 of their study — has doubtless operated in some degree as a 

 cause of this neglect ; for many minds are irresistibly at- 

 tracted by the love of everything that is foreign, while 

 others are fascinated by the possession of complex and ex- 

 pensive apparatus or instruments, which it is beyond the 

 power of the humble observer to purchase. Our own in- 

 vestigations in the forest and on the mountain have too 

 frequently called forth the look of surprise or smile of com- 

 passion to permit us to doubt that such studies are popularly 



