V ON THE FORMATION OF COAL 145 



be untenable when the smaller and the larger sacs 

 are proved to be spores or sporangia. 



Some, once more, have imagined that coal was 

 of submarine origin; and though the notion is 

 amply and easily refuted by other considerations, 

 it may be worth while to remark, that it is 

 impossible to comprehend how a mass of light 

 and resinous spores should have reached the 

 bottom of the sea, or should have stopped in that 

 position if they had got there. 



At the same time, it is proper to remark that I 

 do not presume to suggest that all coal must 

 needs have the same structure ; or that there may 

 not be coals in which the proportions of wood and 

 spores, or spore-cases, are very different from those 

 which I have examined. All I repeat is, that 

 none of the coals which have come under my 

 notice have enabled me to observe such a dif- 

 ference. But, according to Principal Dawson, w r ho 

 has so sedulously examined the fossil remains 

 of plants in North America, it is otherwise 

 with the vast accumulations of coal in that 

 country. 



"The true coal," says Dr. Dawson, "consists principally of 

 the flattened bark of Sigillarioid and other trees, intermixed 

 with leaves of Ferns and Cordaites, and other herbaceous d&bris, 

 and with fragments of decayed wood, constituting ' mineral char- 

 coal,' all these materials having manifestly alike grown and 

 accumulated where we find them." l 



1 Acadian Geology, 2nd edition, p. 138. 

 VOL. VIII L 



