A FEW WORDS ABOUT COAL. 305 



It is natural to ask, says Sir Charles Lyell, whether 

 there were not air-breathing inhabitants of those forest 

 regions where the accumulations of vegetable matter 

 produced the coal-beds ; but, if abundance of carbonic 

 acid gas in the air were a main condition of the great 

 vegetable wealth of the carboniferous period, the pro- 

 bability would seem to be that air-breathing creatures 

 would be few, and those few of the lower orders of 

 animal life. Certain it is that the poverty of the 

 coal-seams in remains of animals has long been com- 

 mented upon by geologists. We find footprints of a 

 monstrous newt, or rather of an animal resembling the 

 tadpole of the newt.* These creatures were truly 

 amphibious, however, sharing the dominion of the 

 water with the ganoid fishes an association which 

 ' reminds us,' says Lyell, c that the living ' creatures of 

 the same order ' in America frequent the same rivers 

 as the ganoids, the bony pikes.' They were un- 

 doubtedly powerful swimmers, Professor Huxley con- 

 siders; and indeed, the main evidence we have of 

 their having been air-breathers is the circumstance 

 that they left footprints on the sand. If they had 

 been walking under water, their weight would have 



* The reader will be reminded of the suggestive remarks, by the 

 author of the Vestiges of Creation, on similar tracks left by the laby- 

 rintkodont of Owen : ' That massive batrachian which leaves its hand- 

 like footsteps in the new red sandstone, and then is seen no more. 

 Not for nothing is it that we start at the picture of that strange im- 

 pression ghost of anticipated humanity for apparently it really is 

 so.' It need hardly be said, however, that this is not the view at pre- 

 sent entertained by naturalists. 



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