Plate 7. 
Figs. 1-8. Mamillopora tuberosa Canu and Bassler, 1919. (See also pi. 6, figs. 16-19.) (p. 192.) 
1. Group showing the upper, lower, and edge views of the zoarium, natural size. 
2. Zoarium with weathered surface, X 20, illustrating that the tuberosities are hollow. 
3. Zooecia, X 20, with one preserving the ovicell, which is hyperstomial and closed by the oper¬ 
culum. 
4. Portion of a zoarium, X 20, with the tuberosities around the zooecial apertures well preserved 
5. Inner surface of zoarium, X 10. The tuberosities, avicularia, and hydrostatic (?) cavities are 
visible. 
6. Portion of figure 5, X 20. 
7. Edge view of fractured zoarium, X 20, illustrating zooecia open. 
8. Similar view, X 20, hut with the zooecia closed. 
Low y er Miocene (Bowden marl): Bowden, Jamaica. 
Figs. 9-14. Holoporella albirostris Smitt, 1872. (See also pi. 32, figs. 6-10.) (p. 174.) 
9. Fragment, X 20, showing zooecia without beak with the typical form of aperture. 
10. Zooecia, X 20, showing interzooecial avicularia. The oral beak is incomplete and in process 
of formation. 
11. Interior of zooecia, X 20. 
12. General aspect of the zooecia with ovicell, X 20. 
13. Marginal zooecia, X 20. The deep zooecia have a beak bearing a small avicularium which 
appears then as isolated. 
14. Zooecia, X 20, showing the different aspects of the beak when broken. 
Lower Miocene (Bowden marl): Bowden, Jamaica. 
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