PLATE LXX. 



pro. 



1. ALCYONIDIUM DISJUNCTUM, p. 497 ; portion of the 

 crust, enlarged. 



2, 3. ALCYONIDIUM MYTILI, p. 498; zooecia. 



4. ALCYONIDIUM HIRSUTUM, p. 493; young colony, 



nat. size. 



5. - , portion of surface, viewed from above, 



showing the zocecial orifices surrounded by the 

 papillae. 



6. , papillae, viewed in profile. 



7. , the polypide. 



8,9. ALCYONIDIUM ALBIDUM, p. 500; portions of crust. 



10. , two zooecia detached. 



11, 12. , polypides. 



