PLATE 72. 



Fig. 1. 679. 3. DiPLOPHYLLUM COKALLIFERUM. ( P^g. 322.) 



1 a. The ends of nnmerous stems of this coral, enclosed in a mass of Stromatopora. 



1 b, c. Enlargements from different cells of this coral. 



Fig. 2. 681. 2. Stromatopora constellata. (Pag. 324.) 



2 a. A portion of the surface of one of these masses, showing the nodose stellate laminae. 



2 b. An enlargement of the surface of two of these iiodes. 



Fig. 3, 4. 680. 1. COLUMNARIA INEQUALIS. ( Pag. 323.) 



3 a. A part of the surface of a small irregular mass, showing fewer young cells than is usual. 

 8 b. Several of the same enlarged. 



4 a. A portion of a specimen showing the prismatic structure of the coral. 

 4 6. A weathered portion enlarged, showing the cellular structure. 



4 c. A reversed figure, the lower extremities of several columns enlarged, showing the mode of weathering, 

 and the structure after the removal of the exterior cellular area. 



