ECONOMIC USES OF LICHENS — LLANO 421 



1^ to 1 hour, depending upon the desired shade of color. Lighter 

 shades are obtained by using weaker solutions. 



AlectoHa juhata. — The color of the horsehair-lichen is gray-brown 

 or black. It grows commonly on old coniferous trees, hanging down 

 from the twigs in long tufts. Its branches, when pulled, do not be- 

 have as do those of the beard-lichen, but, like that lichen, it gives a 

 yellow-brown dye, though of a different tone. 



1. Yellow. — Follow the instinictions as for the beard-lichen. The 

 darkest shade will be mellow green-yellow. By diluting the solution 

 lighter tones of a fine cream-yellow may be obtained. Wash as above. 



Notice ! For obtaining lighter shades of colors the yarn must be 

 boiled six times in weaker solutions. It is not advisable to use 

 stronger solutions for shorter times. This rule can be generally 

 applied in all cases. 



ACKNOWLEDGMENTS 



The author is greatly indebted to Dr. G. Einar Du Rietz, Director 

 of the Plant Science Institute, Uppsala, Sweden, for the many courte- 

 sies received as a student at that Institute ; to Dr. Gunnar Degelius for 

 advice and the generous loan of his valuable collection of books and 

 duplicates; to Dr. Rolf Santesson of the Institute for Systematic 

 Botany for his assistance ; to Dr. Magnus Fries for the use of the Th. 

 M. Fries Lichenological Collection ; to Dr. A. H. Magnusson for the 

 use of his library; and to the librarian of the Carolina Rediviva, 

 Uppsala University, for many favors. Tlie author expresses his ap- 

 preciation also to the American-Scandinavian Foundation, New York 

 City, for the Fellowship which made it possible for him to study at 

 the Royal University of Uppsala, Sweden, from 1946-47; and to Dr. 

 C. W. Dodge, Missouri Botanical Garden, for his kindness in checking 

 the final manuscript of this article. 



The author is greatly indebted also to Miss Carlsson of the Uppsala 

 Hemslojd for her kindness in demonstrating the dyeing technique 

 followed in her classes and in exhibiting materials dyed with lichen 

 dyes. Her advice and suggestions have been incorporated in this 

 paper. Dr. Sten Ahlner, Vaxtbiologista Institutionen, Uppsala, 

 translated "Dye Instructions" for the author, who acknowledges his 

 assistance in this and many other instances. 



LITERATURE CITED 



1. Babby, V. C. Nature, vol. 158, pp. 863-865, 1946. 



la. Barry, V. C, and McNaixy, P. A. Nature, vol. 156, p. 48, 1945. 



2. BtJRKHoLDEB, P. Proc. Nat. Acad. Sci., vol. 30, pp. 250-255, 1944. 



3. BuEKHOLDEB, P., and Evans, A. W. Bull. Torrey Bot. Club, vol. 72, pp. 



157-164, 1945. 



