MUSEUM OF COMPARATIVE ZOOLOGY. G 



Q 



EXPLANATION OF THE PLATES. 



PLATE I. 



Orhicella annularis Dana (natural size). 

 The thickness of the coral at the edge of the mass varies from f to f of an inch. 

 The greatest heiglit of the mass above the cable is 2| inches. 



PLATE II. 



Orhicella annularis Dana (natural size). 

 The thickness of this specimen is very much less than that of Plate I. It varies 

 at the edge of the mass from ^ to J of an inch. The greatest lieight above 

 the cable is 2^ inches. 



PLATE III. 



Mantcina areolata, Ehrenb 



1. Seen in profile. The thickness above the cable is one inch. 



2. Same, seen from above. 



Both figures natural size. 



PLATE IV. 



Isophyllia dipsacea Ag. (natural size) 

 The greatest thickness is 2^ inches 



