.173 



L. polymorphum f. papillata. 

 Fig. 22—23. Habit-figures. 



PL 18. 



L. varians f. verrucosa. 

 Fig. 1 — 5. Habit-figures of the form. 



L. varians f. irregularis. 

 Fig. 6 — 9. Habit-figures. 



L. incrustans f. depressa. 



Fig. 10 — 11. Habit-figure of a French specimen (fig. 10) and a 

 Norwegian (fig. 11). 



L. incrustans f. Harveyi. 

 Fig. 12 — 15. Habit-figures of British specimens of the plant. 



PL 19. 



L. compactum. 



Fig. 1 — 4. Habit-figures of two Norwegian specimens (1 — 2), a 

 Spitzbergian (3) and an American specimen (4). 



L. testaceum. 

 Fig. 5 — 9. Habit-figures of fragments of a crust. 



L. ocellatum. 



Fig. 10. A fragment of the lower branch-system of L. fruticu- 

 losum f. flexuosa or perhaps L. tophiforme infested 

 with this species. 



L. uncinatum. 



Fig. 11. Habit-figure of a fragmentary specimen. 

 „ 12 — 14. Fragments of the same specimen. 



