336 A SYMPOSIUM 



pian ? The repetition of terms involved, if the term sub-Car- 

 boniferous or Lower Carboniferous and Carboniferous continue 

 to be used as now, is so great as to be very confusing to stu- 

 dents. Those who have not dealt with students beginning the 

 study of historical geology may not be aware of the difficulty 

 involved in such a system as the following : 



Carboniferous, 

 Permian, 

 Carboniferous, 

 Sub-Carboniferous. 



9. Would you approve of the separation of the Cretaceous 

 into two divisions coordinate with each other, and each coor- 

 dinate with such divisions as the Devonian ? 



10. If so, would you approve of the retention of the names 

 Lower Cretaceous and Upper Cretaceous, or should one of these 

 divisions, presumably the Lower, receive a new name, say 

 Comanche ? 



11. How should the Cenozoic be subdivided? 



12. What is the advantage of the term Canadian, and the 

 corresponding Trenton, in the following classification ? 



f ( Hudson River 



Trenton 4 Utica 



Ordovician - ■ - -I I Trenton 



Canadian 



Chazy 



Why not instead ? 



[_ l Calciferous 



fHudson River 

 I Utica 

 Ordovician -{ Trenton 



J Chazy 

 ( Calciferous 



13. Will you express your opinion concerning the following 

 outline where the divisions are carried to the second order? 



Era (for time) Period (for time) 



Group (for rocks) System (for rocks) 



f Pleistocene 

 Pliocene 



Cenozoic 



Miocene 



[Eocene 



