IL LUSTRATIONS. 
Text Figures. 
Page. 
Fig. 1. General anatomy of the Clieilostomata 43 
2. Early stages in the development of the Cheilostomata 44 
3 . Sketch showing proliferation of the endoeyst in the Anasca (A) and in the Ascophora (B) . 47 
4. Structure of the olocyst 48 
5. Structure of the tremocyst 49 
6. Microstructure of the tremocyst and olocyst 50 
7. Structure of the tubules 51 
8. Structure of the pleurocyst 52 
9. Septulae and dietellae 53 
10. Diagram showing structure and terminology of the ovicells 55 
11. Passage of the eggs 57 
12. Hydrostatic functions 59 
13. Structure of the avicularium 62 
14. Structure of the vibraculum 65 
15. Structure of the vestibular arch, etc 69 
16. Sketch illustrating structure of the Malacostega 73 
17. Family Electrinidae D’Orbigny, 1851. 74 
18. Genus Electra Lamouroux, 1816 76 
19. Genus Membranipora Blainville, 1834. 78 
20. Genus Heterooecium Hincks, 1892 79 
21. Genus Pyripora D’Orbigny, 1852 .-. 79 
22. Genus Herpetopora Lang, 1914 81 
23. Structure of the Membraniporae 83 
24. Genera of Membraniporae without ovicell 85 
25. Genus Conopeum Norman, 1903 86 
26. Genus Adenifera Canu and Bassler, 1917 101 
27. Genera of Membraniporae with endozooecial ovicell 109 
28. Genus Hincksina Norman, 1903 Ill 
29. Genus Membrendoecium Canu and Bassler, 1917 120 
30 . Membraniporae with hyperstomial ovicells, always closed by the opercular valve 124 
31. Genus Ellisina Norman, 1903 126 
32. Genus Grammella Canu, 1917 130 
33. Genus Tremopora Ortmann, 1890 139 
34. Genus Larnacius Norman, 1903 140 
35 . Genera of Membraniporae with ovicells never closed by the opercular valve , 141 
36. Genus Alderina Norman, 1903 142 
37. Genus Callopora Gray, 1848 146 
38. Genus Amphiblestrum Gray, 1848 157 
39. Genus Earn phono tus Norman, 1894 163 
40. Genus Tegella Levinsen, 1909 166 
41. Miscellaneous genera of Membraniporae _ 174 
42. Genus Cauloramphus Norman, 1903 174 
43. Genus Ammatoph ora Norman, 1903 175 
i The plates of this Bulletin, 162 in number, with their explanations, have been bound for convenient reference as a sep- 
arate volume. 
XV 
