[ami] SYNOPSIS OF THE GEOLOGY OF CANADA 211 
The Union and Riversdale formations appear to lie unconformably 
below the limestones, gypsum and marls of the Windsor formation. 
Overlying these Eo-Carboniferous rocks in Nova Scotia, there occur 
marine limestones and gypsum associated with limestone conglomerate 
and shales, and sandstones, and sandstone-conglomerates, commonly 
described as a “Lower Carboniferous Series.’ The most fossiliferous 
limestones, as at Windsor and Brookfield, have been referred to the 
Windsor formation, but a number of limestone bands of this series have 
been described by C. F. Hartt and Sir Wm. Dawson, from various locali- 
ties in the same province under various designations and from researches 
carried on by the writer during the past five years in Nova Scotia, there 
is no doubt that several distinct horizons in the Carboniferous are 
marked by the different calcareous or limestone bands. 
The Windsor formation is followed upward or accompanied by an 
extensive series of sandstone conglomerates and grits, or freestone, to 
which the term “ Millstone Grit” formation has been applied. In the 
Pictou Coal Field the writer has recognised and described the Westville 
formation, equivalent to the so-called “ Millstone Grit” of that district, 
which former name is suggested, inasmuch as the true and original 
“Millstone Grit” of England is doubtfully equivalent to the series 
of strata referred to the same name in Canada. The freestones and 
conglomerates of the Westville formation as developed along the 
Joggins shore, below the productive Coal Measures of Cumberland 
county are extensively used in the manufacture of grindstones and 
polishing materials. The Stellarton formation is the name applied to the 
shales, sandstones and associated coal-bearing strata of the “Coal 
Measures” of Pictou county as developed at Stellarton, on East River, 
along McLellan’s brook and at the Acadia and other mines in Westville. 
The sedimentation in the Joggins region was remarkably different 
from that which we find in the Pictou basin, although not so far apart, 
and it may be advisable for the sake of accuracy and more exact defini- 
tion to give different geological names to these two sets or series of strata 
occurring in these two districts at a later date. 
Above the productive Coal Measures in the Joggins section (which 
section is probably the most complete and uninterrupted in Eastern 
America belonging to this system, being upward of 14,000 feet in 
thickness) we find more sandstones and shales, with conglomerates which 
are well developed along the east side of the Cumberland basin. 
In Pictou county, unconformably above the Westville formation the 
New Glasgow conglomerates (New Glasgow formation) form a conspicuous 
feature in the Carboniferous sequence, as the basal series of a continuous 
section of strata extending from New Glasgow to Northumberland straits, 
