PLATE XVII. 



Orbitolites. — Alveolina. 



Diatn. Page 



Figures 1-6. — Orbitolites complanata, Lamarck, sp., . x 12 219 



Monstrous specimens, sliowing the results of 

 redundant and inequilateral growth. 



., 7-12. — Alveolina boscii, Defrance, sp., .... 222 



Figs. 7-9. Lateral aspect ; fig. 10, terminal aspect, . x 15 



Fig. 1 1 . Longitudinal section of the shell, . . x 25 



Fig. 12. Transverse section of the shell, . x 25 



,, 13-15. — Alveolina melo, Fichtel and Moll, sp., . x 50 223 



Fig. 13. a, Lateral aspect ; b, terminal aspect. 

 Fig. 14. Longitudinal section of the shell. 

 Fig. 15. Transverse section of the shell. 



