PLATE II. 



Kig. I. A specimen of Monticulipora {Htieroirypa) gracilis, James, from the Cin- 

 cinnati group of Ohio, of the natural size. 

 Fig. I a. Surface of the same, enlarged eighteen times. 

 Fig. I b. Small portion of the surface of the same, enlarged fifty times. 

 Fig. 2. A specimen oi Monticulipora {Hctcrotrypa) ramosa, D'Orb., of the natural 



size. From the Cincinnati group of Ohio. 

 Fig. 2 a. Surface of the same, enlarged eighteen times. 

 Fig. 3. A specimen of Monticulipora rugosa, Edw. and Haime, of the natural 



size. From the Cincinnati group of Ohio. 

 Fig. 4. A specimen of Monticulipora Dalii, Edw. and Haime, of the natural 



size. From the Cincinnati group of Ohio. 

 Fig. 5. A specimen of Monticulipora {Afonotrypa) briarea, Nich., of the natural 



size. From the Cincinnati group of Ohio. 

 Fig. 5 a. Tangential section of the same, enlarged eighteen times. 

 Fig. 5 b. Fart of the preceding section, enlarged fifty times. 

 Fig. 5 c. Vertical section of the same, enlarged eighteen times. 

 I'^ig. 6. Fragment of the crust of Monticulipora {Feronopora) Cincinnatiensis, 



James, of the natural size, showing the prominent monticules. From the 



Cincinnati group of Ohio. 

 Fig. 6 a. Part of the surface of the same, enlarged eighteen times. 

 Fig. 6 b. Part of a tangential section of the same, enlarged eighteen times, 



showing the large tubes with their incomplete tabulae and the intercalated 



small tubes. 

 Fig. 6 c. Vertical section of the same, enlarged eighteen times, showing the 



incomplete tabula; of the large tubes. 

 Fig. 7. A specimen of Monticulipora {Hctcrotrypa) implicata, Ulrich, of the 



natural size. From the Cincinnati group of Ohio. 

 Fig. 7 a. Fractured extremity of the same specimen, enlarged three times, 



showing the arrangement of the tubes. 

 Fig. 7 b. Portion of the surface of the same, enlarged eighteen times. 

 Fig. 7 c. A small part of the surface of the same, enlarged fifty times, showing 



the prominent blunt spines (spiniform corallites) between the large tubes. 

 Fig. 7 d. Tangential section of the same, enlarged eighteen times. 

 Fig. 7 c. Part of a vertical section of the same, enlarged eighteen times. 



