Plate 4. 



Figs. J, 2. Rhynchozoon vnii<ihani Cami and Basslor, 1919. iSoo also pi. 2, fig. 22.) (p. I.5.J.) 



1. The unilamellar zoarium, X 20, showing young condition in which the zooecia are distinct. 



2. Old condition of zoarium, X 20. The zooecia are indistinct and not oriented. 

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



Figs. 3-12. Metrarabdotos coUigatum Canu and Bassler, 1919. (p. 162.) 

 3 5. Different as])ects of the base of the zoarium, X 6. 

 (). Three fragments, natural size, preserving base. 



7. Portion of zoarial surface, X 20, with ovicells well preserved. 



8. Base of a zoarium, X 20, showing calcification and disappearance of the apertures. 



9. Broad zooecia, X 20, characteristic of the aged condition. 



10. Narrow zooecia, X 20, of youthful condition. 



11. Normal zooecia, X 20. 



12. Longitudinal section, X 20, exhibiting the interior of the zooecia. 

 Lower Miocene (Bowden horizon): <^'ercado de Mao, Santo Domingo. 



Fig. 13. PalmkeUaria cf. inmnis Jullien, 1882. (p. 149.) 



The branching fragment referred doubtfully to this species, X 20. 



Lower Miocene i Bowden horizon I : Santo Domingo. 

 Fig. 14. Rhynchozoon curium, new species, (p. 15G.) 



The unilamellar zoarium, X 20, illustrating the characteristic short zooecia. 



Lower Miocene (Bowden horizon t: Santo Domingo. 



248 



