PLATE XXIII. 



Figure 1. Leptoria concentrica, Duncan. The corallumj natural size. 

 3. Septa, magnified. 



3. Trochocyathus Gajensis, Duncan. Side view of coral, natural size. 



4. The base and costae, slightly magnified. 



5. Antillia plana, Duncan. The corallum, natural size. 



6. Stylophora minuta, var., Duncan. Calices, magnified. 



7. Stylophora confusa, Duncan. Calices, magnified. 



8. Cladocora Haimei, Duncan. Side view of pieces o£ a coraUum. 



9. Calice, magnified. 



10. Dasyphyllia, species. Part of a corallum, natural size. 



