Plate (!. 



Fio. 1. Lnhiopora 7niocc7iicn Canu and ISasslrr, 1919. (p. 67.) 



Frafjniont of the unilamellar zoariiim, ■: 20. The polypidiam tube and tlic small pores of the 

 tremocyst are visil>lc. 



Lower Miocene i Bowden horizon i: Kio (iuralio, Santo Domingo. 

 Fig. 2. Hippomenella infratehnn Canu and Bassler, 1919. (p. 132.) 



Base, of the bilaniellar zoarium, X 20. One zooecium is regenerated, being replaced by an 

 avicularium. 



Lower Miocene ( Bowden horizon ) : Cercado de Mao. Santo Domingo. 

 Figs. 3-5. Sehizopodrella mulabilu Canu and Bassler. 1919. (p. 105.) 



3. The tubular zoarium, natural size. 



4. Surface, X 20, showing indistinct zooecia. 



5. Another.portion of the same zoarium, X 20, illustrating the shape of the zooecia. 

 Lower Miocene (Bowden horizon): Cercado de Mao, Santo Domingo. 



Figs. G-9. Steganopordla parvicella Canu and Bas.sler, 1919. (p. G2.) 



6. Fragments of the unilamellar zoarium, natural size. 



7. Zoarial fra,gment, X 20, illustrating the great irregularity in the zooecia. 



8. The usual zooecia, X 20, with regular arrangement. 



9. The most frequent aspect of the zooecia, X 20. Tlie ])olyi)idian tube is very fragile and often 

 broken or altered. 



Lower Miocene (Bowden horizon): Cercado de Mao, Santo Domingo. 

 Figs. 10-15. ThaUimopnreUa bipfr/onita Canu and Bas.sler, 1919. (p. 02.) 



10. Fragments of the bilaniellar zoarium, natural size. 



11. Specimen, X 20, exliilriting a well-preserved reticulocellarium. 



12. An example, X 20, showing the hollow tubercles worn and replaced by pores. A reticulocel- 

 larium is here present. 



bi. Drawing showing the real form of the aperture, X 77. 



14. A specimen, X 20, ■with a deformed membraniporoid zooecium near the ujiper corner. 



15. Another similar example. ;~- 20. with a prinioserial memltranijioroid zooecium along the lower 

 edge. 



Lower Miocene ( Bowden horizon) : Cercado de Mao and Rio Cana. Santo Domingo. 

 FiG.s. 1(;-19. -VomjT/opora ri/fcfro.so Canu and Bassler. 1919. (Seeal.so pi. 7, figs. 1-8.) (p. 192.) 



11!. Small fragments of the small, free, conical zoarium, natural size. 



17. Zoarial fragment, X 20, with large zooecia. 



IS. Fragment, X 20, with small zooecia. The ttibercles are well developed. 



19. Inner side of zoarium, X 20. 



Lower Miocene (Bowden horizon): Rio Cana, Santo Domingo. 

 Figs. 20, 21. Dicipemecin milnmna D'Orbi.gny, 1839. (p. 202.) 



View s of a fragment, natural size and X 12, referred to this siiecies. 



Lower Miocene (Bowden horizon): Cercado de Mao, Santo Domingo. 

 Figs. 22, 23. Adeona porosa Canu and Bassler, 1919. (p. 15S.) 



l'"ragment of the free bilaniellar zoarium, natural size and X 20. 



In figure 23, three gonoecia with their oral gibbosities are shown in the upper right-hand corner, 

 an avicularian zooecium in the upper left-hand corner, and ordinary zooecia with their ascopores, 

 and small areolae in the rest of the photograph. 



Lower Miocene (Bowden horizon): Cercado de Mao, Santo Domingo. 



250 



