EXPLANATION OF PLATES. 



193* 



PLATES V & V A. 



EXPLANATIONS OF ADDITIONAL FIGURES. 



i^ 



Fio 



i^T 



■ PLATE V. 

 CHEMUNG GROUP. 



DlCTrOPHTTON CONRADI. 



2. The dorsal view, the narrower side on the exterior carve. The figure is two- 

 thirds the natural size. 



DlCTYOPHYTON RUDE. 

 8. A portion of the surface of a stem : natural size. 



Fig 

 Fig 

 Fio 



Fio 



Fio 



Pemphigaspis bulla^a. 



8. The upper surface. 

 ,4. The lower surface. 



, 5. Profile view from the posterior extremity. 

 The figures are six times enlarged. 



Amphion? matutina. 

 6. The glabella and part of one fixed cheek. The figure is four times enlarged. 



CONOCEPHALITES OPTATUS. 

 ,7. The glabella and part of fixed cheeks : six times enlarged. 



