20 



POPULAR HISTORY OP LICHENS. 



which it has hitherto remained, of the neglect which it has 

 hitherto suffered. Instead of advancing science, the labours 

 of earlier Lichenologists more frequently constituted barriers 

 to its progress, for later authors have been chiefly occupied 

 in correcting the errors, supplying the omissions, and 

 clearing from the field the 



" Rudis indigestaque moles" 



of crude theories accumulated by their predecessors. Thus, 

 though much has been written, little real progress has been 

 made until within a comparatively recent period. We may 

 now be said to be entering on a new era in Lichenology ; 

 it is now being studied in a more philosophic spirit, and 

 with all the aids w 7 hich modern discoveries in science — 

 which the microscope and chemistry — can furnish. Tacts 

 are being earnestly and patiently sought after ; generaliza- 

 tion and theory avoided until a sufficiency of data be accu- 

 mulated to form a firm foundation for the superstructure 

 of classification ; and a determination is being evinced to 

 overcome all the obstacles and difficulties w r hich naturally 

 beset a subject which has been rendered so intricate, and 

 which is now being stormed as a fortress that has success- 

 fully withstood the repeated assaults of scientific observers ; 

 and moreover we believe the labourers are increasing and 



