PLATE XVIII. 



Figure 1. Eurhodia Mobrisii, D'Archiac and Haime (page 70). The test, from above, natural 

 size. 



2. Side view, natural size. 



3. Transverse outline. 



4. Actinal surface, natural size. 



5. Apical system, magnified. 



6. A portion of an ambulacrum, magnified. 



7. The peristome and its ornamentation, magnified. 



