PLATE XIV. 



Fig. T. Portion of a vertical section of MontiaiUpora (Diplotrypa) Whiteavesii, 

 Nich., from the Trenton Limestone of Peterboro', Ontario, enlarged twenty 

 times, showing the closely-tabulate small corallites, and the twofold con- 

 stitution of the tabulje of the large corallites. 



Fig. 2. Part of a tangential section of MonticuUpora {Monotrypa) Wintai, 

 Nich., from the Devonian Limestone of Gerolstein in the Eifel, enlarged 

 twenty times, showing the tliin-walled polygonal corallites, with an occa- 

 sional young tube intercalated. 



Fig. 2 a. Part of a vertical section of the same, showing the thin walls, and the 

 uniform development of the tabulce of all the corallites. 



Fig. .3. A medium -sized specimen of Monticulipoi-a (^Monoirypa) iindtilata, 

 Nich., from the Hudson River Group of Toronto, Ontario, of the natural 

 size. The specimen is broken on one side. 



Fig. 3 (7. Part of a tangential section of the same, enlarged twenty times, show- 

 ing the thin-walled, and nearly equal-sized corallites. 



Fig. 3 b. Part of a vertical section of the same, enlarged twenty times, show- 

 ing the thin and undulated walls, and the uniform development of the 

 remote tabulce. 



Fig. 4. Part of a tangential section of Mojiticulipora (A'lonotrypa) iindulata, 

 Nich., from the Trenton Limestone of Peterboro', Ontario, enlarged 

 twenty tmies. 



Fig. 4 a. Part of a vertical section of the same, enlarged twenty times, showing 

 the thin undulated walls, and the remote tabulse placed at corresponding 

 levels. 



Fig. 5. One of the star-like elevations of the surface of CoiutcUaria antheloidea , 

 Hall, from the Cincinnati Group of Ohio, enlarged. 



F'ig. 5 a. Part of a tangential section of the same, taken just below the surface, 

 enlarged twenty times. The upper part of the portion figured traverses 

 one of the stellate areas or "maculae," while the lower part cuts across a 

 portion of the general surface. 



Fig. 5 /'. Part of a vertical section of the same, showing the two sets of coral- 

 lites, enlarged twenty times. 



Fig. 6. Part of a tangential section of a typical example of Moiiiiculipora ptd- 

 chella, E. and H., from the Wenlock Limestone of Dudley, enlarged 

 twenty times. The section cuts across one of the clusters of large 

 corallites. 



Fig. 6 a. Small portion of a longitudinal section of the same specimen, show- 

 ing the characters of the corallites just before they open on the surface, 

 enlarged twent)' times. 



