Plate 23. 



1-4. Poroeidaris variabilis A. Ag. and Clark. 

 1. Abactinal view of partly cleaned, light-colored specimen. 

 U. Actinal view of same. 



3. Ambulacral view uf same. 



4. Interambulacral view of same. 



5-8. Aporocidaris fragilis A. Ag. and Clark. 



5. Abactinal view of cleaned test. 



6. Actinal view of same. 



7. Interambulacral view of same. 



8. Ambulacral view of same. 



All figures natural size. 



