418 



Plate XXIV. 



Fig. 1 a. Conescharellina philippensis (Busk). Five 

 zooecia are seen from the basal side (after 

 tlie removal of the frontal wall) showing a 

 number of avicularian chambers, which 

 are connected partly with the zooecial sur- 

 face and partly with each other through 

 rosette-plates and pore-channels. There is 

 also seen one of the peculiar kenozooecia, 

 which are provided with a narrow semilu- 

 nate aperture. X 75. 



— 2 a. Discopora Sarsi (Smitt) from Tassiusak, 



East-Greenland. The ooecia show a more or 

 less developed ooecial cover. X 40. 



— 3 a. Hippopodina feegeensis (Busk). X 40. 



— 3 b. The same species with avicularia but with- 



out ocecia. X 40. 



— 3 c. The same species with another form of 



avicularia. X 40. 



— 3d. The same species with the avicularia in 



another position. X 40. 



— 3 e. A mandible of the same species. X 75. 



— 3 f. A zooecium with ooecium of the same spe- 



cies, seen from the left side-wall. X 40. 



— 4 a. Cheilopora sincera (Smitt). Two zooecia with 



ooecia seen from the left side-wall. X 23. 



— 5 a. Smittina foliacea (Ellis & Sol.), with ooecia. 



Only a very small proximal part of the 

 ectoooecium can be seen, and the rest is 

 concealed by a tripartite ooecial cover (see 

 pag. 64). X 40. 

 Fig. 6 — 18. In the following diagrammatic represen- 

 tations of different hyperstomial ooecia the 

 black colour designates the calcareous parts, 

 the red the membranaceous and the non- 

 coloured portion the muscular. The dotted 

 lines are only hypothetical. Reference letters : 

 av. avicularium. ecto. Ectoocecium. endo. En- 

 ooecium. Cr. Cryptocyst. c. m. Covering mem- 

 brane op. Operculum, o. o. Ooecial opercu- 

 lum, o. c. Ooecial cover, v. Vestibulum. 



— 6. Flustra membranaceo-truncata (Smitt). 



— 7. Flustra flustroides (Hincks). 

 8. Flustra foliacea L. 



— 9. Columnaria borealis n. sp. 



— 10. Onychocella sp. 



— 11. Urceolipora nana Mac Gill. 



— 12. Onchopora Sinclairi (Busk). 



— 13. Bugula sp. 



— 14. Thalamoporella sp. 



— 16. Emballotheca quadrata (Mac Gill.). 



— 16. Callopora aurita (Hincks). 



— 17. Schizoporella unicornis (Johnst). 



— 18. Myriozoum coarctatuih (Sars). 



