28. 

 29. 



30. 

 31. 

 32. 

 33. 



28, 29. Strongylocentrotus fragilis Jackson. 



X 70. 



Side view of valve of globiferous pedicellaria. 

 Base of same. X 70. 



30-33. Strongylocentrotus polyacanthus A. Ag. and Cl. 



Tridentate pedicellaria. X 70. 



Side view of blade of valve of globiferous pedicellaria. 



Base of a similar valve. X 70. 



Valve of ophicephalous pedicellaria. X 70. 



X 70. 



1 1 



