HISTORY OF LICHENOLOGY. 



23 



and that the Lichens are merely the result of the decom- 

 position of a higher vegetation. Such ideas, which may be 

 regarded as foreshadows of, or as analogous to, the pro- 

 gressive-development theories of more modern times, how- 

 ever ingenious in themselves and attractive from their ap- 

 parent simplicity, could not for a moment stand the test of 

 experience. They originated in, and were fostered by, the 

 speculative dispositions of the German school of observers. 

 Sprengel, who very beautifully designates the Cryptogamia 

 as the "secret recesses of Nature's sanctuary/' speaks of 

 many of the Lichens as " formed of nothing but pure pre- 

 cipitation from the vegetable juices, except here and there 

 some slight rudiments of a cellular organization." 



In reviewing briefly the onward progress or history of 

 Lichenology in Europe, we may regard it as divisible into 

 three eras, the first dating about the year 1700, and marked 

 by the labours of Tournefort ; the second occurring about 

 the year 1800, and characterized by the voluminous and 

 valuable works of Acharius ; and the third commencing 

 about 1850, and distinguished by the important monograph 

 of Tulasne. Prior to the date of the first era above alluded 

 to, the Lichens were included indiscriminately, under various 

 names, among Mosses or Fungi. By Tournefort, in his c In- 



