PLATE 4.: 



FiGTJRE 19. Another of the same. (X 120.) 



Figure 20. Horizontal section of the same. (X 120.) 



Figure 21. Horizontal section of the same. (X 180.) 



Figure 22. Horizontal section of Torbanite. (X 120.) 



Figure 23. Horizontal section of boghead from Autun. (X 120.) 



Figure 24. Vertical section of boghead from Autun. (X 120.) 



