304 



the basal conglomerates are beds of limy grey and 

 green shales and other conglomerates. Many intrusive 

 bodies, in the form of dykes and sheets, cut the formation. 

 At Pleasant valley and in the vicinity of Maryvale in the 

 Big Marsh, the upper portion contains beds of oil shale 

 (Ells, 1908), which with associated beds have a thickness 

 of 125 feet (38 m.). Plant fragments are present in these 

 shales, but in the shore sections no organic remains have 

 been found. There is hardly any doubt that the deposits 

 are of continental origin and were laid down in the old 

 erosion channels. Fletcher gives the thickness as 1145 

 feet (346 m.). 



Ardness formation. — ^This formation begins with about 20 

 feet (6 m.) of limestone, thin-bedded at the summit and 

 base, but compact near the centre. The remaining more 

 than 2000 feet (610 m.) consist of sandstone, shale and 

 marl. The prevailing color is red and the sandstones are 

 ripple marked. Along the line of the Intercolonial rail- 

 road near Antigonish the bed of limestone is overlain by 

 about 200 feet (60 m.) of red sandstone and shale which are 

 followed by about an equal thickness of gypsum. The 

 bed of limestone is certainly of marine origin while the 

 gypsum was probably deposited in arms of the sea having 

 slight connection with the parent body. In the shore 

 section there is no evidence for considering the beds above 

 the limestones of other than continental origin. From 

 the limestones Williams obtained fossils which Schuchert 

 identified as Beecheria davidsoni {Terehratula sacculus 

 Davidson), Martinia glabra, Pugnax sp., Productus cf. 

 douhleti, and P. dawsoni. The thickness of the formation is 

 2045 feet (622 m.) (Williams). 



Pennsylvanian. 



Listmore formation.- — -The name Listmore has been pro- 

 posed by Williams for a series of sandstones and shales, 

 generally of red color which lie in apparent conformity on 

 the Ardness formation. The deposits are of continental 

 origin and contain imperfect specimens of Stigmaria and 

 Calamites as the only organic remains. The thickness is 

 982 feet (299m.). 



With this formation the sedimentary record closes and 

 there were no other deposits laid down in the Arisaig region 

 till the advent of the ice sheets when irregular masses of 



