Geol. Mag. 1874. 



New Seeies. 



Decade II. Vol. T. Pl. II. 



Fig. 1. 





® ®® <s 





Fig. 2. 



Fig. 1, — Callopora incrassata, 'Nich. a. A fragment, natural size. 6. A portion of the surface 

 magnified, showing the calices and ccEnenchymal tubuli. c. A portion of the surface less highly- 

 magnified, showing one of the vacant areolae surrounded by coralUtes. d. Vertical section of a 

 fragment enlarged. From the Hamilton Group. 



Fig. 2. — Alveolites frondosa, Nich., partially restored in outline, natural size, a. A fragment 

 of the surface magnified. From the Hamilton Group. 



