1865.] DAWSON — COAL-FOEMATION. 105 



have had reference principally to the appearances presented by the 

 Coal-formation of Nova Scotia, and that I have no wish to under- 

 value the admirable researches on this subject of Brongniart, 

 Goeppert, Hawkshaw, Beaumont, Binney, Kogers, Lesquereux, and 

 others, whose publications on this subject I have read with interest, 

 and have tested in their application to the phenomena presented to 

 me in the coal-fields of Nova Scotia. I may add that in my opinion 

 the phenomena of the Stigmaria-underclays, to which attention was 

 first directed by Sir "W. E. Logan, furnish the key to the whole 

 question of the origin of coal, and that the comparisons of Coal- 

 deposits, by Sir Charles Lyell, wdth the "Cypress-swamps" of the 

 Mississippi perfectly explain all the more important appearances in 

 the Coal-formation of Nova Scotia. 



§ III. Details of the Character and Fossil Contents of the several 

 Beds of Coal, as exposed in the South Joggins Section. 



1. Introduction. — Under this heading I propose to state all the 

 facts bearing on the origin and mode of formation of the several coals, 

 obtained either by careful study of their outcrops on the ground, or 

 by subsequent examination, with the aid of the microscope, of speci- 

 mens collected from them. I shall follow the order of the detailed 

 section published by Sir W. E. Logan in 1845*, including the ad- 

 ditional points observed by Sir C. Lyell and myself in 1852, and by 

 myself in several successive visits t, but giving in minute detail only 

 the coals and their associated roof-beds and underclays. The sand- 

 stones and shales which constitute the mechanical filling-in between 

 the beds of coal I shall group together in the shortest possible manner, 

 referring to the published sections above-mentioned for details. I 

 shall, however, mention every case of the occurrence of beds holding 

 erect trees, and of Stigmarian underclays, as well as of beds of bitumi- 

 nous limestone and highly carbonaceous shale. I regard the former as 

 being truly land-surfaces, as well as the coals, and the latter as 

 accumulations of vegetable mud or muck which imply the contem- 

 poraneous existence in their vicinity of swamps and forests. 



2. Logmv's Section (order descending), a. Division 1. — This ex- 

 tends along the coast from Shoulie Eiver to the vicinity of Ragged 

 Beef, being nearly horizontal at the former place and gradually 

 assuming a decided south-west dip towards the latter. It is 1617 

 feet in vertical thickness, and constitutes the upper part of the 

 *' Upper Coal-formation." It occupies the centre of the great syn- 

 clinal of the western part of the Cumberland coal-area, and presents 

 the newest beds of the Carboniferous system. 



The rocks are thick-bedded white and grey sandstones, passing 

 in some places into conglomerates with quartz pebbles, and inter- 

 stratified with reddish and chocolate shales. The sandstones pre- 

 dominate. 



Eossils are not numerous in these beds. Those found are Dadoxy- 



* Report of Progress of Canadian Survey, 1845. 



t Quart. Journ, Geol. Soc. vol. x. ; also Acadian Geology, p. 128 et seq. 



