Fig. 13. — Eudendrium californicum. Blastostyle. with young hydranth 

 fastened to its stalk. 



Fig. 14. — Same species. Young blastostyle. 



Figs. 15-20. — Hydractinia milleri. 



Fig. 15. — Sterile hydranths. x 27. 



Fig. 16. — Distal portion of fertile hydranth with six tentacles, x 90. 



Fig. 17. — Fertile hydranths with three tentacles, x 27. 



Fig. 18. — Large sterile hydranth; proboscis contracted, club-shaped, x 27. 



Fig. 19.— Spine, x 30. 



Fig. 20. — Sterile hydranth, showing arrangement of tentacles in quartettes. 



Fig. 21. — Corymorpha palma. Gonophore. 



