EXPLANATION OF PLATE VIII. 



Fig. 1. Trochus { iScalwtrochus) lindstriJmi, Eth. fil. Side view of a some- 

 what damaged specimen. 



2. The same. Ventral view. 



3. Niso, sp. Cross section of an example from tlie Tertiary l)eds of 

 Muddy Creek, Victoria — x 7. 



4. Niso (Vctoiuba) brazieri, Eth. fil. Cross section. 



5. The same apex downwards, and partly in section. 



G, Favositcs grandipora, Eth. fil. Four corallites in section, showing 

 the single row of large pores in one of the walls of each — x 5. 



7. The same. Horizontal section, showing forms of the calices, 

 remains of the proper wall, and secondary thickening — x a. 



8. The same. Portion of the natural surface of a corallum — x G. 



9. The same. Horizontal section of unthickened tubes — x 6. 



