Plate XX. 



Fig. i. Tridentate pedicellaria of Echinus Alexandri. Obj. o. Oc. I. 



— 2. Spicules of Echinus Alexandri. Obj. V. Oc. I. 



— 3. Valve of a triphyllous pedicellaria of Strongylocentrotus drebachiensis. Obj. II. Oc. III. 



— 4. — — tridentate - i.granulatus. Obj.o. Oc. I. 



— 5. ophicephalous - Obj. II. Oc. III. 



— 6. — tridentate - Obj. o. Oc. I. 

 7. triphyllous - Sterecliinus Neumayeri. Obj. II. Oc. III. 



— 8. Spicules of Echinus elegans. Obj. V. Oc. I. 



9. Tridentate pedicellaria, small form, of Echinus elegans. Obj. II. Oc. o. 



10. Valve of a tridentate pedicellaria of Strongylocentrotus pulcherrinius. Obj. II. Oc. o. 



— n. Tridentate pedicellaria of Slerechinus Neumayeri. Obj.o. Oc. I. 



— 12. Spicules of Strongylocentrotus drebachiensis. Obj. V. Oc. I. 



— 13. Sphaeridia of Obj. II. Oc. III. 



14. Valve of a globiferous pedicellaria of Strongylocentrotus purpuratus, from the inside. Obj. II. Oc.o. 



— 15. Globiferous pedicellaria of Psammechinus variegatus. Obj. II. Oc.o. The skin full of spicules. 

 16. Valve of a globiferous pedicellaria of Strongylocentrotus drebachiensis , from the inside. 



Obj. II. Oc. I. 



— 17. Spicules of Echinus af finis. Obj. V. Oc. I. 



— 18. Sprueridia of Strongylocentrottis drebachiensis. Obj. II. Oc. III. 



— 19. Tridentate pedicellaria, large form, of Echinus elegans. Obj. o. Oc. o. 



— 20. Valve of a tridentate pedicellaria of Strongylocentrotus drebachiensis. Obj. o. Oc. I. 



— 21. — triphyllous - Echinus af finis. Obj. II. Oc. III. 

 22. - elegans. Obj. II. Oc. III. 



— 23. Stalk of a globiferous pedicellaria of Echinus elegans. Obj. II. Oc. I. 



— 24. Spine from the buccal plates of Echinus esculentus. Obj. o. Oc. o. 



— 25. Globiferous pedicellaria, the neck protruded, of Strongylocentrotus drebachiensis. The spicules 



are drawn only on the upper side of the head. Obj. o. Oc. I. 



- 26. Valve of a globiferous pedicellaria of Strongylocej/trolus drebachiensis, from the side. Obj. II. Oc. I. 



— 27. • ophicephalous — large form, of Echinus Alexandri. Obj. II. Oc.o. 



• 28. - globiferous of Strongylocentrotus purpuratus, from the side. Obj. II. Oc. o. 



- 29. Globiferous pedicellaria, the neck retracted, of Strougyloc. drebachiensis. Obj. o. Oc. III. 



- 30. Spine of Echinus esculentus, the basal part. Obj. o. Oc. o. 



