n8 



THE HABITAT OF THE EURYPTERLDA 



or no eurypterid remains, but more marine organisms. That the Ber- 

 tie eurypterids lived in the rivers is thus indicated, while their absence 

 from the Rosendale could be explained by assuming that the present 

 exposures of these rocks are in the more marine portion of the deposit. 

 The relations are shown in the following diagrams (figs. 5 and 6). 



6. THE KOKOMO WATERLIME 



The Kokomo waterlime of Indiana is of very much the same char- 

 acter as the Bertie waterlime, showing the same thin laminations and 

 fine texture. Throughout a limestone series forty feet thick thin 

 waterlime layers occur and it is in these alone that the films of euryp- 



Seo, level 



Fig. 5. Ideal N. W.-S. E. Cross Section from Buffalo, N. Y. to Tyrone, 

 Pa.., Showing Conditions During Bertie Time 



Fig. 6. Generalized Cross-Section of the Same Region Showing Present 

 Conditions due to Post-Bertie Deposition and Erosion 



terid exoskeletons are found. In the pure limestones a brachiopod 

 fauna occurs, but no eurypterids are present; while in the separating 

 waterlime eurypterids and ceratiocarids, but no brachiopods are 

 found. Foerste has made the following statements in regard to the 

 occurrence: "At the McReynold or Interurban quarry, in the south- 

 western corner of Kokomo, there is a much thicker exposure of the 

 upper or brachiopod horizon. No merostomata have been found here. 

 " South of the center of Kokomo within the town limits, there is a 

 deep quarry, covering a considerable area, where merostromata are 

 common at an elevation of 3 to 3! feet above the base of the quarry. 

 This belongs to the lower thinly laminated part of the section, and 

 the richly fossiliferous brachiopod beds appear to be absent" (Foerste, 

 67, 7). ' 



