PLATE XI. 



Figure 1. Feddenia typicAj Duncan. The corallunij side view, natural size. 



2. A part of a calicej magnified. 



3. Costse and part of epitheca, magnified. 



4. Feddenia typica, variety 1. Septa, magnified. 



5. Granules on a septum, magnified. 



6. Feddenia typica, variety 2. The corallum, natural size. 



7. Costse and septa, magnified. 



8. Feddenia cristata, Duncan. The corallum, natural size. 



9. Trochoseris dipfobmis, Reuss. The corallum, natural size. 



10. Septa, magnified. 



11. LiTHAR^A GRANDis, Duucau. The corallum, natural size. 



12. Calices, magnified. 



13. Reticulate appearance of costse on the base, magnified. 



14. MoNTLivALTiA Granti, J. Haime. The corallum, natural size. 



15. Septa, magnified. 



16. Costse, exotheca, and epitheca, magnified. 



17. A small and young specimen, natural size. . 



