212 
REPORT OF THE AMERICAN COMMITTEE. 
Conclusion. 
In consonance with these views and recommendations your 
reporter would present the following scheme : 
The whole of the strata included between the Devonian and 
the Archean would thus fall into three great groups. 
Silurian. 
Cambrian. 
Taconic. 
Under the term Silurian fall the American strata known as : 
SILURIAN. 
Fauna! (systemic) 
designations. 
Rooii masses of New York. Serial designations, 
based on structure and physical breaks. 
a 
3 
OS 
CO 
1 
a 
'E 
3 
»5 
Lower Helderberg limestones and Salina shales. 
Lower Hel- 
derberg. 
Niagara. 
Niagara limestone and shale. 
Clinton. 
Clinton limestone and shales. 
Medina sandstone and shales. 
Under the term Cambrian fall the 
CAMBRIAN. 
Faunal (systemic) 
designations. 
Rock masses and structural designations of New 
York. 
c3 
a 
3 
a 
■73 
1 
C 
'S 
a 
O 
JS 3 
Lorraine [Hudson River] shales and limestones. 
1. Lorraine. 
2. Utica. 
Utica shale. 
3. Trenton. 
Trenton limestones and shales, Bird's Eye, Black 
River and Chazy limestones. 
Upper part of Calciferous sandrock. 
