PLATE XXXIII. 



Rhynchopygus paci&cus,/. 1, 2. 



1. Interior view of actinal surface. 



2. Interior view of abactinal surface. ' 



Laganum depressum, f. 3, J^. 



3. Interior view of actinal floor. 



4. Interior \'iew of abactinal surface. 



Rotula August!,/. 5. 



5. Seen from above, to show the actinal floor. 



Echinocardium cordatum, /. G. 



6. Abactinal part of the anterior odd ambulacrum seen from the interior of the test 



Schizaster caualiferus, /. 7. 



7. Petals seen from, the interior of the test. 



{All Figs, natural size.) 



