Carhoniferous System of the United States. 417 



mian, and thence into the upper Permian. About 27 per cent, 

 of the carboniferous pass into the Permian.* 



During all the period of the deposition of the rocks under 

 consideration, one law of life, with its succession of species, 

 seems to liave prevailed ; while at the same time there was one 

 law of geological deposition. There is no abrupt change, all 

 is orderly and easy in its sequence. Faunas familiar to us, 

 through all the carboniferous seas, follow us into the Permian, 

 and there we lose them for ever. 



The same floras from peat bogs, oozy marshes, or sandy ridges, 

 are seen in every roof stratum of shale or sandstone. There is no 

 sign of change either in stratiiication, conformity, or palaeon- 

 tology. Why should one be called Carboniferous, another Sub- 

 carboniferous, and still anotlier, Permian ? 



In this connexion another coal-bearing stratum comes into 

 view, which there is more difficulty to place in the newly enlarged 

 boundaries of the carboniferous. I allude to the coal of North 

 Carolina and Kiclimond, Virginia. According to H. D. Ro- 

 gers, the coal of Virginia belongs to the Jurassic series. "With 

 him agrees Sir Charles Lyell. William B. Rogers thinks that 

 this coal is of the age of the Triassic. Dr. Emmons, whose faci- 

 lities for examining the beds of North Carolina were diligently 

 improved, classes the Deep and Dan river beds with the Per- 

 mian. Prof. Ileer, a very competent authority, sustains him 

 in this opinion. The great want of conformability of the red 

 sandstone of the Atlantic slope, with the coal of the Apalachian 

 systems, makes this part of our inquiry one of very great dif- 

 ficulty. 



Prof Emmons' argument for the Permian relationship of 

 these coal strata is derived, 



* Since writing the above my notice has been called to a paper of Mr. Thomas 

 Davidson, of England, upon the occurrence in the Permian of carboniferous fos- 

 sils, and he cites the following, Martinia clannyana, Spiriferina crista, Carnaro- 

 phoria scklofhehni, C. globulina, Lingula credneri. To this catalogue of molluscs, 

 Mr. J. W. Kirby adds the following Crustacea, Cythere elongata, C. ornata, Bairdia 

 gracilis, Ggrocanthus formo.iux. 



