Hides (Hid Misrules in Classification. — Marcou. 115 
been contented to give the classification of strata, as they 
make it out by stratigraphy, it would liave given to their work 
a character of impartiality, at the same time a true value, 
which no controversy would have been able to make use of, 
except to quote the facts well observed and clearly described. 
Here is the series and its classiiication as given on the 
Map of Greylock and Hoosac Jfountains, to illustrate the Ge- 
ological structure of the Green Mountains 1891, Plate I : 
f Greylock schist. 
Silurian ■[ Bellowspipe limestone. 
I Berkshire schist. 
l^ Stockbridge limestone. 
Cambrian Vermont formation. 
( 
The Stockbridge limestone is divided in two, the lower part 
being classified as Lower Cambrian (Lower Taconic) and the 
upper part as Lower Silurian (Champlain or true Cambrian 
of Sedgwick, or Ordovician), a most extraordinary compound 
of a group of strata, absolutely incorrect and materially im- 
possible. But more, the geological map is obscured by a 
double classification of two formations, one called "Rowe 
schist," referred to the Silurian, and the other called "Hoosac 
schist," referred to the Silur-Cambrian. As no explanation 
of that double classification exists on the map, the reader in 
order to understand it must look at p. 13, a figure called 
"Correlated columns of the Hoosac and Greylock rocks." 
Here it is in the form of a table : 
Greylock Mt. Hoosac Mt. 
Greylock schist Rowe schist. 
Bellowspipe limestone i 
Berkshire schist ^ Hoosac schist. 
Stockbridge limestone \ 
Greylock Mt. and Hoosac Mt. are separated only by a nar- 
row valley. It is to be expected that the authors would see 
such lithologic difference between the strata forming opposite 
mountains that they would have come to the conclusion I 
have constantly advocated since 1862, that there are at mount 
Greylock lenticular masses or islets of magnesian limestone 
(Stockbridge and Bellowspipe limestones) inclosed in the 
slates (Berkshire and Greylock schists). 
We are constantly confronted in that memoir with the ex- 
pression "Lower Silurian fossils," but not a single one is 
