2 HISTORY OF LICHENOLOGY 



A seventh period which includes modern lichenology, and which dates 

 after the publication of Krempelhuber's History, was ushered in by 

 Schwendener's announcement in 1867 of the hypothesis as to the dual 

 nature of the lichen thallus. Schwendener's theory gave a new impulse to 

 the study of lichens and strongly influenced all succeeding investigations. 



B. PERIOD I. PREVIOUS TO 1694 



Our examination of lichen literature takes us back to Theophrastus, 

 the disciple of Plato and Aristotle, who lived from 371 to 2846.0., and who 

 wrote a History of Plants, one of the earliest known treatises on Botany. 

 Among the plants described by Theophrastus, there are evidently two 

 lichens, one of which is either an Usnea or an Alectoria, and the other 

 certainly Roccella tinctoria, the last-named an important economic plant 

 likely to be well known for its valuable dyeing properties. The same or 

 somewhat similar lichens are also probably alluded to by the Greek phy- 

 sician Dioscorides, in his work on Materia Medica, A.D. 68. About the 

 same time Pliny the elder, who was a soldier and traveller as well as a 

 voluminous writer, mentions them in his Natural History which was 

 completed in 77 A.D. 



During the centuries that followed, there was little study of Natural 

 History, and, in any case, lichens were then and for a long time after 

 considered to be of too little economic value to receive much attention. 



In the sixteenth century there was a great awakening of scientific 

 interest all over Europe, and, after the printing-press had come into 

 general use, a number of books bearing on Botany were published. It will 

 be necessary to chronicle only those that made distinct contributions to the 

 knowledge of lichens. 



The study of plants was at first entirely from a medical standpoint 

 and one of the first works, and the first book on Natural History, printed 

 in England, was the Crete Herball 1 . It was translated from a French work, 

 Hortus sanitatis, and published by Peter Treveris in Southwark. One of 

 the herbs recommended for various ailments is "Muscus arborum," the 

 tree-moss (Usnea). A somewhat crude figure accompanies the text. 



Ruel 2 of Soissons in France, Dorstenius 3 , Camerarius 4 and Tabernae- 

 montanus 8 in Germany followed with works on medical or economic botany 

 and they described, in addition to the tree-moss, several species of reputed 

 value in the art of healing now known as Sticta (Lobarid) pulmonaria, 

 Lobaria laetevirens, Cladonia pyxidata, Evernia prunastri and Cetraria 

 islandica. Meanwhile L'Obel 6 , a Fleming, who spent the latter part of his 

 life in England and is said to have had charge of a physic garden at 



1 Crete Herball 1526. 2 Ruel 1536. 3 Dorstenius 1540. 



4 Camerarius 1586. 5 Tabernaemontanus 1590. 8 L'Obel 1576. 



