25-27. Clypeaster rotundus (A. Ag.). 



25. Valve of triphyllous pedicellaria. X 300. 



26. Side view of valve of small tridentate pedicellaria. X 300. 



27. Valve of tridentate pedicellaria. X 70. 



28-31. Clypeaster virescens Dod. 



28. Blade of valve of ophicephalous pedicellaria. X 70. 



29. Large tridentate pedicellaria. X 70. 



30. Interior view of loop of valve of ophicephalous pedicellaria. X 70. 



31. Interior view of loop of large valve of ophicephalous pedicellaria. X 





