132 



THE GENUS MONTICULIPORA. 



Obs. — In common with various American observers, I have 

 formerly identified the present form with the AI. Flctchcri, 





iMg. 22. — Moiiticuliporci Ulrichii, Nich. (the so-called M. Flctchcri of the Cincinnati forma- 

 tion). A, A fragment of the corallum of the natural size ; ]'., Part of the surface, enlarged 

 eighteen times ; C, Tangential section of the same, similarly enlarged ; D, Part of a 

 tangential section, enlarged fifty times, showing the two sets of corallites, and the tubular 

 spines ; E, Part of a vertical section, enlarged eighteen times. From the Cincinnati 

 Group, Cincinnati, Ohio. 



Edw. and Haime, of the Wenlock Limestone of Britain.^ I 

 am, however, now satisfied that the examples from the Cin- 

 cinnati Group certainly cannot be properly thus identified, with 

 our present knowledge. We are not at present acquainted 

 with the minute structure of the type-specimens upon which 

 the distinguished French writers above mentioned founded the 

 species ]\I. Flctchcri, so that any identification of these with 

 the form now under consideration is necessarily exceedingly 



1 After a careful investigation, I have failed to satisfactorily identify any of the 

 specimens in my collections from the Wenlock Limestone with M. Fleicheri, E. 

 and H. Judging from external characters only, there were several specimens which 

 I should have thus identified ; but on making a microscopic examination of these by 

 means of thin sections, I found these to be really referable to a species of Fistu- 

 lipora, and to be therefore, at any rate, entirely distinct from the so-called AI. 

 Fletclieri of the Cincinnati Group. 



