[amr] SYNOPSIS OF THE GEOLOGY OF CANADA 208 
stones, are well exposed, and present a compact fauna, which in 
facies closely resembles rocks in Herefordshire, in Cumberland, West- 
moreland, in the Kendal and Ludlow regions of England. The “Knoy- 
dart” formation consisting of red shales and sandstones and calcareous 
bands holding pteraspidian and ostracoderm fishes and crustaceans refer- 
able to the Cornstone or lower Old Red sandstone of Great Britain, 
almost immediately overlies the Silurian strata, though no. actual con- 
tact has been observed. The Silurian series at Arisaig consists of at 
least four distinct geological formations. Beginning above we have first 
the “ Stonehouse” formation, consisting for the most part of dark red, 
fine-grained shales and mudstones, holding a conspicuous lamellibran- 
chiate fauna, of which Grammysia Acadica, Billings, is a well known 
species, together with a number of interstratified more or less thin 
calcareous bands holding brachiopods, gasteropods, trilobites and ostra- 
cods in abundance. Below this we find the “ Moydart” formation, 
which consists of more or less heavy-bedded, light greenish gray and 
rusty-weathering calcareous strata (in which the “Red Stratum” of 
authors occurs) and holds brachiopods, gasteropods, cephalopods and 
crinoids. Beneath this again we have the “ McAdam” formation, con- 
sisting for the most part of impure black carbonaceous shales, which are 
splintery at times, holding a lamellibranchiate fauna and graptolites. 
At the base occurs the “ Arisaig” formation, which comprises buff- 
weathering, fine-grained compact sandstones and shales, containing 
corals (chiefly Streptelasma), brachiopods, gasteropods and trilobites. 
The thorough investigation of this series of strata, which indeed, may 
require further subdivision, is expected to furnish data bearing on the 
settlement of the mooted question as to where the Silurian stops and the 
Devonian of America.* 
In the county of Annapolis, Nova Scotia, and in the vicinity of 
Nictaux, Silurian strata occur including the Nictaux iron ore beds and 
the Torbrook sandstone formation, whilst. near Kentville, the Kentville 
formation is seen as well as on Angus Brook in the Gaspereau Valley, 
also at New Canaan, with Dictyonema Websteri, Dawson, and at 
Wolfville in King’s county where coralline limestones, red and green 
graptolitic slates, and other strata at times highly cleaved, squeezed and 
metamorphosed form conspicuous ridges, and constitute the oldest sedi- 
mentaries in the vicinity of the Bay of Fundy and the Blomidon region 
in the “ Land of Evangeline.” 
In Cumberland county, along the northern slope of the Cobequids, 
isolated areas of Silurian strata have been mapped out and described by 

1 Remarks on subdivisions of Arisaig Silurian are inserted after going to 
press.—H. M. A. 
Sec. IV., 1900. 11. 
