Plate 11. 



1-5. Acanthocidaris hastigera A. Ag. and Clark. 



1. Valve of globifei'ous pedicellaria. x 156. 



2. Valve of small globiferous pedicellaria. x 150. 



3. Valve of another small globiferous pedicellaria. x 156. 



4. Valve of tridentate pedicellaria. x 55. 



5. Exterior view of base of valve of tridentate pedicellaria. x 55. 



0-12. Anomocidaris tenuispina A. Ag. ami Clark. 



6-10. Valves of small globiferous pcdicellarite, showing the great diversity in form and 

 size. X 55. 



11. Tip of valve of small globiferous pedicellaria, showing absence of end-tootli. x 156. 



12. Tip of valve of small globiferous pedicellaria, showing presence of end-tooth, x 156. 



