THE LICHEN-FLORA OF CHICAGO AND VICINITY. 15 



Part I., 1882. A close study of these will show how very near he 

 came to nature in his reading of her laws as applied to the lichens, 

 and how well he succeeded when he came to their arrangement. 

 The key to his success may be found in his expression — " Ap- 

 prehension of the Habit of Lichens." This was certainly an in- 

 spired faculty and led him to forecast the relations of lichens by 

 which they could be placed in the system he established, as Tribes, 

 Families, Groups, Genera, Species, etc. The one great American 

 Lichenologist is dead, but the services performed cannot be over- 

 estimated. Part II. of his Synopsis, left incomplete at his death, 

 which occurred March 15, 1886, was edited and published by Henry 

 Willey, Tuckerman's life-long collaborator, in 1888. The foregoing 

 were by no means all of Tuckerman's works, but they are the most 

 important, on which rests the solid basis of his fame. As a supple- 

 ment to the labors of Tuckerman, American Lichenology has been 

 benefitted by Henr}^ Willey, in his publication, " Synopsis of the 

 Genus Arthonia, " and his introduction to the " Study of Lichens," 

 but these must be considered rather as aids to be used in connec- 

 tion with the study of other authors. While the publications 

 mentioned are the chief ones in this country, monographs upon a 

 single genus, or species, have appeared from time to time; also 

 local lists and brief papers, and these evince the interest awakened, 

 which no doubt received its impelling force from a knowledge of 

 the genius and labors of Tuckerman. 



THE ECONOMIC USES OF LICHENS. 



A few remarks on this subject will show how large a part 

 these seemingly humble plants play in the economy of life. The 

 Reindeer Moss (Cladonia rangiferina) furnishes not only food for 

 the reindeer in the Arctic regions, but alcohol and brandy are 

 distilled from it by the natives of Norway, Sweden and other 

 countries. The Iceland Moss (Cetraria Islandica) has long been 

 in use, both for food and medicine. Cetraria nivalis is also eaten. 

 In Africa Lecanora esculenta is so abundant on sandy plains^that 

 it is gathered for food for man and beast. Many Arctic voyagers 

 have prolonged and saved their lives by the use of species of 

 Umbilicaria — rock-lichens {Tripe-.de roche). In Japan a species of 

 the genus Endocarpon,, also common in Illinois, is used as food. 

 Valuable dyes were formerly obtained from several lichens, such as 

 Roccella tinctoria, Lecanora tartaraea, Parmelias, etc. The new 



