THE PERMO-CAEBONIFEROUS. 35 



have steeper dips than the south-east sides, and consequently occupy 

 a less breadth on the map. The south-east sides also show the best 

 and most continuous sections; and for this reason I shall select the 

 section from New Glasgow to Pictou Harbour, and that from Carribou 

 Harbour towards Cape John, as typical of the lower and upper parts 

 of the Upper Coal formation. 



Section on the East River of Pictou. 



1. In the river section, below New Glasgow bridge, the conglo- 

 merate is succeeded in ascending order by a gray concretionary lime- 

 stone 20 feet thick, associated with sandstone and shale, and containing 

 in some layers great numbers of the Spirorbis, which I have described 

 as S. arietinus,* and whose habits of life were probably not dissimilar 

 to those of S. carbonarius, so abundant in the Coal-measures. This 

 limestone does not appear in the immediate river section, but on the 

 flank of the conglomerate east of New Glasgow. 



2. Above this is a series of black shales and underclays with gray 

 sandstones and some reddish and purple shales, and thin seams of 

 bituminous shale and coal. These beds contain Stigmariaz, Lepido- 

 dendra, Entomostracans, and fish-remains; the fossils and the mineral 

 character of the beds alike corresponding with those seen in the upper 

 part of the Coal-measures south of the conglomerate. The thickness 

 of these beds is about 400 feet. 



3. This series is succeeded by a thick gray sandstone holding 

 Catamites, Calamodendron, trunks with aerial roots (Psaro7iius), etc., 

 30 to 50 feet thick. This appears at the mouth of JSinelt Brook, and 

 in several quarries to the eastward of that place. 



4. Above this is a second series of dark shales and underclays, and 

 bituminous shales associated with gray sandstones, and containing 

 fossils similar to those of the series below. It especially abounds in 

 fish-scales and Cythere ; and several of the fishes ara specifically 

 identical with those of the upper part of the Middle Coal-measures, 

 as seen in the southern trough south of New Glasgow. These beds 

 are about 200 feet thick. Mr II. Poole has described them in the 

 "Canadian Naturalist" for August 1860. 



5. The beds up to this point may be considered the equivalents 

 of the Middle Coal-measures, or of the upper part of them, and are 

 now succeeded in ascending order by thick gray and reddish sand- 

 stones, and reddish and gray shales, including, however, thin coaly 



* Report of Geol. Survey of Canada. This limestone may be compared with the 

 "Spirorbis limestone " of the Shrewsbury, Lancashire, and Warwickshire Coalfields 

 in England. Hull, " Coal-fields of Great Britain." See also Note 3, p. 102. 



(J 



