124 Barrande and the Taconic System — Marcou. 
word is "error" of Mr. Hall in tr3'ing io transfer the 
Primordial fauna above the second fauna. 
V. 1861. — W. E. Logan says: the Quebec group is the equiva- 
lent of the Chazy and Calciferous; it is brought to the 
surface by an overturn anticlinal fold with a crack and 
a great dislocation running along the summit. This 
dislocation proceeds from lake Champlain to Quebec, 
keeping just north of the fortress, theace it coasts the 
north side of the island of Orleans, and from the east 
end of the island it keeps under the water of the St. 
Lawrence; — a leap in the water. 
VL 1862. — James D, Dana says: light came in again through 
the Vermont Geological Survey. Now in the report of 
this survey the Red sandrock is regarded as the equiva- 
lent of the Medina group, the Georgia slates of the 
Oneida conglomerate, and the Stockbridge limestone as 
Devonian and Carboniferous . So according to Mr. Dana 
the referring the Georgia slates with their Primordial 
fauna by Messrs. Hitchcock to the Upper Silurian is 
''light." 
Vn. 1862. — Charles H. Hitchcock proposes the "Georgia group'* 
on account of the existence of the trilobites found in the 
township of Georgia, and he does not know where the 
Parker's quarry is situated, coloring on his geological 
map the whole part of the township of Georgia in which 
the Primordial fossils exist as Oneida conglomerate, or 
Upper Silurian; a "confusion" unique in the proposal 
of typical localities for a group in geology. 
VIIL 1877. — Hall and Dana say: the eastern quartzite forma- 
tion is of the age of the later Tre)iton or Cincinnati 
group; and Dana adds, or "younger." 
IX. 1879.— A. R. C. Selwyn says: that the anticlinal fold of 
Logan is a synclinal and that it is a mistake to make it 
"pass to the rear of the Quebec citadel," for it passes in 
fronts but under the river. Mr. Selwyn kept his "great 
St. Lawrence and Champlain fault," from the south of 
the city of Quebec to the middle of the Gulf of St. Law- 
rence, where he stops it, constantly under water; another 
leap in the water. 
X. 1888.— Charles D. Walcott 'discovers a "Potsdam off-shore 
