1865.] 



DAWSON — OOAIi-FORMATION. 



123 



n. 



(Reddish shale and sandstone with one underclay 

 r Reddish underclay with Stigmaria. 



ft. in. 

 35 



Coal-group 43. . . •< Coaly shale 1 inch 1 



|_ Reddish underclay, Stigmaria. 



This bed diminishes to a mere film towards the bank. 



Coal-group 44 . . . ■< 



(Reddish, grey, and dark shales and sandstone, Stig- 

 maria in some beds, and erect Sigillarice and 



Ca/amzYes at one level) 63 



( G-rey shale with ironstone. 



Bituminous limestone and shale with ironstone, 10ft. 1 in. 



Coal \ inch. 



Bituminous limestone, Stigmaria, ^ inch. ' 



Coal 5 inches. 



Bituminous limestone, Stigmaria, 2 inches. 



Coal 1 inch. 



Bituminous limestone, Stigmaria, 2 inches. 



CoaHinch 11 0^ 



^ Argillo-arenaceous underclay, traces of rootlets. 



The bituminous limestone has scales of fishes, JSpirorhis, 

 and Oyihere. The coal has Cordaites and vascular bundles 

 of ferns. 



(Red and grey sandstone and shale. One underclay, 



and erect Ca^aweYes at one level) 98 6 



^Reddish shale. 

 Carbonaceous shale, 10 inches. 

 Coaly matter ^ inch. 

 Hard imderclay, Stigmaria, 2 feet. 

 Coaly matter ^ inch. 

 Underclay, Stigmaria, 7 feet. 



Coal 3 inches 10 2 



^ Arenaceous underclay, Stigmaria. 



In the roof of the lower coal is an erect tree. The coal has 

 vascular bundles of ferns, remains of fern-leaves, and bast 

 tissue. The underclay has many coaly films, apparently 

 flattened bark of trees. 



Reddish and grey sandstone and shale 5 6 



Coal-group 45... 



Total thickness of Division 4, according to Logan's measurements 2539 1 



e. Division 5. — This consists of reddish shales and red and grey 

 sandstones. It contains no coal, and is poor in fossils, only a few 

 drifted trunks appearing in the section. It corresponds to the upper 

 part of the Millstone-grit series. Its thickness, according to the 

 measurements of Sir "William E. Logan, is 2082 feet. 



f. Division 6. — This may be regarded as the middle of the Mill- 

 stone-grit series. It constitutes a sort of false coal-formation, sepa- 

 rated from the Middle Coal-formation by the barren beds of Division 5. 

 It contains nine small or rudimentary coal-beds, which, however, are 

 not well seen in the section, and have afforded few facts of interest. 

 It has many thick and coarse sandstones and much red shale, with 

 comparatively few dark-coloured beds. Its total thickness is stated 

 by Sir W. E. Logan at 3240 feet. 



