484 



GEOLOGY OF THE YELLOWSTONE NATIONAL PAEK. 



All the evidence available seems to indicate that the Madison limestone 

 is faunally a unit and can not be subdivided on the basis of its contained 

 fossils. 



Although the fauna comprises many Kinderhook species, I doubt 

 whether it can justly be regarded as representing the Kinderhook alone; 

 possibly it is equivalent to the major portion of the Mississippian. The 

 exact correlation of this fauna has proved impossible, but its affinities 

 seem to be rather with the Kinderhook than with any other division of the 

 Lower Carboniferous. 



The following table represents the various species of invertebrates 

 recognized in the Madison limestone and their range through the nine beds 

 whose character and succession have just been described. The table is 

 defective in that a number of localities from which collections were made 

 have not been located in the section scheme previously given, and conse- 

 quently the data so furnished could not be tabulated. And again, the 

 collections from many localities are so meager as not to contain, probably, 

 many of even the commoner species. Other sources of error exist in the 

 possibility of incorrect reference of the localities to their true horizon in the 

 section, and of mistaken identifications in the course of paleontologic work. 

 Much care has been taken to minimize both these sources of error, and it is 

 believed that the accompanying table is a fair statement of the character 

 and range of the fauna of the Madison limestone. 



Table showing the range of Lower Carboniferous species. 





Number of bed. 





24 | 



25 



26 



27 



28 



29 



30 



31 



32 





















X 





























X 

























X 







X 











X 



X 







X 





X 

 X 















Menophyllum (?) excavatuoi n. sp 



X 





X 



X 

 X 

 X 





X 



X 











X 





X 

 X 



X 



X 

 X 







X 









? 











X 























X 





