EXPLANATION OF PLATE 2 



Fig. 1-5 Transverse sections showing types of inner walls; fig. 4 is a dissepimental stereotheca; 

 fig. 5 is a septal stereotheca. 



6-12 Transverse (above) and longitudinal (below) sections showing types of axial columns. 



13-15 Transverse sections showing types of fossulae. 



16-19 Transverse sections showing appearances of various septal groups. 



20 Transverse section of one corallite and portions of surrounding corallites in a phaceloid 

 corallum. 



21-24 Transverse sections of one corallite and portions of surrounding corallites in plocoid 

 coralla. 



24 



