ILLUSTRATIONS. 



PLATES. 



Facing page. 



Plate 68. Gyrophora polyphylla (L.) Borr. & Turn, and G. rugifera (Nyl.) Th. 



Fries 315 



69. Gyrophora reticulata (Schaer.) Th. Fries 316 



70. Gyrophora vellea (L.) Ach. and G. polyrhiza Koerb 317 



71. Gyrophora hyperborea (Iloffm.) Ach 319 



72. Gyrophora phaea (Tuck.) Herre 320 



73. Umbilicaria pustulata (L.) Hoffm 321 



FIGURE. 



Page. 



Figure 56. Diagram of Lake Ellia 326 



VII 



