Reports and Proceedings. 79 



was read : — " On the Conditions of the Deposition of Coal, more 

 especially as illustrated by the Coal Formation of Nova- Scotia and 

 New Brunswick." By J. W. Dawson, LL.D., F.R.S., F.G.S. 



In several former papers Dr. Dawson has endeavoured to illustrate 

 the arrangement of the Carboniferous rocks of Nova Scotia, and to 

 direct attention to their organic remains, the structures found in the 

 coal, and the evidence which they afford as to the mode of accumula- 

 tion of that mineral. In this paper the author summed up and 

 completed his researches, adding some new facts resulting from the 

 study of the microscopic structure of more than seventy beds of coal 

 occurring in the South Joggins section, and of the fossil plants 

 associated with them. 



Some general considerations relating to .the physical conditions of 

 the Carboniferous period in Nova Scotia were first given, the author 

 dividing the strata representing that period into (1) the Upper Coal- 

 formation, (2) the Middle Coal-formation, (3) the "Millstone-grit" 

 formation, (4) the Lower Carboniferous marine-formation, and (5), 

 the Lower Carboniferous Coal-measures, describing the characters of 

 these divisions in detail, and giving a sketch of the physical condi- 

 tions which prevailed during their deposition. He was of opinion 

 that we must regard each of the above-mentioned divisions as the 

 evidence of a period presenting during its whole continuance the 

 diversified conditions of land and water, with their appropriate 

 inhabitants, and as forming a geological cycle in which such con- 

 ditions were to a certain extent successive. 



As in previous publications, so in this, Dr. Dawson contended that 

 the occurrence of Stigmaria under nearly every bed of coal proves 

 beyond question that the material of the coal was accumulated by 

 growth in situ, while the character of the intervening strata proves 

 the abundant transport of mud and sand by water ; in other words, 

 the conditions implied are such as prevail in the swampy deltas of 

 great rivers. He also stated that the coal consists principally of the 

 flattened bark of sigillaroid and other trees, mixed with leaves of 

 ferns, Cordaites, etc., and other herbaceous debris ; and that the 

 Cannel Coal and Earthy Bitumen are of the nature of the fine vegetable 

 mud which accumulates in the ponds and shallow lakes of modern 

 swamps. 



In the succeeding portions of the paper the author gave details of 

 the character and contents of the several beds of coal in the Joggins 

 section, arranged in the order of Sir W. E. Logan's sectional list, 

 and made some remarks on the genera of animals and plants, whose 

 remains occur in the coal, and on their evidence as to the mode of its 

 accumulation. 



The following objects were exhibited : — A new Form of Gonio- 

 meter ; exhibited and explained by Prof. N. S. Maskelyne, M.A., 

 F.G.S. Bone from a Peat-bed near Wareham, Dorsetshire ; exhibited 

 by the Rev. J. H. Austen, M.A., F.G.S. Fossils from Trmidad and 

 Anguilla ; exhibited by E. Lechmere Guppy, Esq. 



11. — January 10, 1866. — W. J. Hamilton, Esq., President, in the 



