G2 
ANNALS NEW YORK ACADEMY OF SCIENCES 
The top of the calyx was ground smooth and polished. A dot of ink was 
placed on this polished surface right at the end of each of the ink lines on the 
side of the corallite. These three dots marked the upper exposed end of the 
three principle septa. The corallite was then cemented by this polished sur¬ 
face to a piece of plate glass and sawed off as close as possible to the glass. 
The thin slice cemented to the plate glass was ground down, transferred and 
mounted as a transparent microscopic section, the dots of ink all the while 
marking the identity of the three principle septa and being unaffected by 
the heat and substance used in cementing and mounting. The process 
Fig. 25a-g. Enterolasma caliculum. (Enlarged.) 
was repeated as often as possible, and as many sections as could be made 
were cut from a single corallite. Figures 25 and 26 show seven sections 
each made from two individuals in this manner. In the first and last section 
of each, the principle septa were not identified. The intermediate stages, 
however, are well shown. In these microscopic sections, a permanent record 
is preserved of all observations made, but the development cannot be fol¬ 
lowed step by step through all its minutest details as it was by the process of 
grinding down from the tip and sketching each step as it was encountered, 
at the same time destroying one stage in order to get the next. 
