1886. ] MADREPORARIAN CORAL. 131 
Fig. 4 Fig. 5. 
Diagrams of the arrangement of the septa in the five different species of 
Stephanotrochus. The septa are numbered. 
1. S. nobilis. 2. S. platypus. 3. S.diadema. 4, S. discoides. 5. S.moseleyanu 
