GRAPTOLITID.E. 



155 



No. 490. G-raptolithiis (Monoprion) clintonensis, Hall. 



In this genus the polypidom is a 

 long, narrow blade with a row of 

 cells on one side. Clinton Group, 

 Rochester, N. Y. 



No. 491. Climocograptus typicalis, Hall. 



The cells of this genus appear to have their mouths sunk, the surface of 

 the polypidom forming a row of openings on each side. Cincinnati Group, 

 Cincinnati, Ohio. 



No. 492. Diplograptus pristis, Hall. 



In this genus the polypidom possesses a row of cells on each side. This 

 and the preceding genus range from the Cambrian to the Upper Silurian. 

 Utica Slate, near Utica, New York. 



