MR. STANLEY SMITH ON 



[Jlarch 191 3, 



commencing at the point where the reduction of the central column 

 begins (PL IX, fig. 2). 

 A sudden reduction of the zone of dissepiments at a point a little 

 farther from the proximal end of the coralluin than where the changes 

 in the central column are first observed. The result of this is a 

 diminution in the diameter of the coralluin, as shown in text-fig. 8 

 (p. 73) and in PI. IX, fig. 2 ; also compare PI. IX, fig. 1 b with 1 c. 



00 -> 





=0 ■» 





C5 g> 



VI. The termination of the original septa, and the formation of new septa 

 upon their rounded edges. The latter are cemented upon the former 

 by stereoplasm, which extends as thin irregular plates for some 

 distance down the first-formed septa as well as up the new septa, as 

 seen in fig. 9 (above). The extension of the cementing stereoplasm 

 appears as thin threads at the sides of the septa. 



