126 THE PERMIAN. 



but there is every reason to believe that it was of long duration. 

 Again, in connection with this, the relations of the Trias to the 

 Carboniferous show that the latter must have experienced much 

 denudation by aqueous agency prior to the deposition of the former. 

 Lastly, the study of the distribution of the Trias over the shores of 

 the Bay of Fundy shows, as already stated, that, previous to the 

 Triassic period, that Bay had already assumed in some measure of its 

 present form, and, consequently, that the Carboniferous beds had 

 already in part been elevated into land. All these facts give us 

 evidence of lapse of time — of tune occupied in this locality not by 

 aqueous deposition, but by physical movements, probably of elevation, 

 and by denuding action. That this time corresponded to that of 

 the Permian elsewhere, no one who believes in the contemporaneous- 

 ness of the Carboniferous of America with that of Europe can doubt. 

 The possibility, however, still remains that Permian beds may have 

 been deposited in some parts of the area, and may have been removed 

 by denudation, or may be covered by the Trias or by the sea. This 

 is, however, only a mere possibility, so long as no traces of these 

 beds can be discovered. 



Again, it is possible that the conditions of the Upper Coal Formation 

 may have continued longer in America than in Europe, and, con- 

 sequently, that this part of the Carboniferous may synchronize with 

 the Permian of Europe and with that of Western America. This 

 raises the question of " Homotaxis," as it has been called, or similarity 

 of arrangement as distinguished from actual contemporaneity. An 

 able palaeontologist has said that, "for anything that geology or 

 palaeontology can show to the contrary, a Devonian flora and fauna 

 in the British Islands may have been contemporaneous with Silurian 

 life in North America, and with a Carboniferous fauna and flora 

 in Africa. Geographical provinces and zones may have been as 

 distinctly marked in the Paleozoic epoch as at present." I must 

 maintain, however, that no such uncertainty exists as to the Carbon- 

 iferous period. In America, its flora was homogeneous from New- 

 foundland to Alabama, and from the Atlantic Coast to the Rocky 

 Mountains, evidencing a uniformity of climate unparalleled in modern 

 times. Its succession of zones of vegetation, from that of the lower 

 coal-measures upward, is preserved over all this area ; and when we 

 find it existing in all its detail in Europe, and with a majority of the 

 species the same, it would be most rash to suppose that the times of 

 this succession were not identical. Farther, it seems impossible 

 to doubt that this uniformity was caused by prevalent climatal 

 conditions which could not have been local ; as, for instance, by a 



