876 SCIENCE. [N. 8. Vox. X. No. 259. 
THE NEW YORK SERIES. 
ERA oR SYSTEM. PERIOD OB GROUP. AGE OB STAGE. 
( Georgian 
Cambric 
or 4 Acadian 
Taconic 
| Potsdamian 
{ Canadian (3) 
(Paleochamplainic) 
Ohamplainic (1) | Mohawkian(4) 
(Lower Silurian and 4 (Mesochamplainic) 
Ordovician ) 
Cincinnatian (5) 
( Neochamplainio) 
f Oswegan (6) 
| ( Paleontario) 
Ousetis (2) J viagaran (7) 
Siluric | ( Mesontaric) 
| Cayugan (8) 
L (Neontaric) 
f °o 
| ‘3 [ Helderbergian (9) 
a4 
|= 
3 | Oriskanian (10) 
Ay 
=f 
| § | Ulsterian (11) 
S | 
3 | 
Werone j S  Erian (12) 
ee 
& | Senecan (13) 
5 | 
3 
|= 
| wy 
i 
l Chautauquan (14) 
grit. Vanuxem and Hall terminated the division 
above with the Niagara, Emmons included the Salina 
and waterlime. Any rational grouping of these for- 
mations must recognize as its base the predominance 
Georgia slates 
Potsdam sandstone and limestone 
JS Beekmantown limestone (15) 
\ Chazy limestone 
Lowville limestone (16) 
Black river limestone 
Trenton limestone 
Lorraine beds (17) 
Richmond beds (Ohio and Indiana) 
| Utica shale 
Oneida conglomerate 
Shawangunk grit 
Medina sandstone 
{ Clinton beds 
Rochester shale 
Lockport limestone 
Guelph dolomite 
1 
Salina beds 
Rondout waterlime (18) 
Manlius limestone (19) 
{ Coeymans limestone (20) 
| New Scotland beds (21) 
| Becraft limestone (22) 
l Kingston beds (23) 
Oriskany beds 
Esopus grit (24) 
Schoharie grit 
Onondaga limestone 
Marcellus shale 
Hamilton beds 
{ ‘Tully limestone 
| Genesee shale 
Portage beds 
1 (Naples beds, 
| Ithaca beds, 
l Oneonta beds, 
local facies) 
(Catskill sandstone, (25) 
local facies) 
| Chemung beds 
of coarse sedimentation installing a new cycle. Grow- 
ing evidence fully endorses Emmons’ view as to the 
termination of the group and period with the clearing 
of the Salina sea. 
