W. H. Twenhqfel — Peat Beds of Anticosti Island. 65 



Art. V. — Geologic Bearing of the Peat Beds of Anticosti 

 Island I by W. H. Twenhofel. 



[Contributions from the Paleontological Laboratory of Yale University.] 



Introduction. 



Inferences as to the method of deposition of the vegetable 

 matter forming coal liave developed two rival hypotheses : 

 the one arguing for deposition of the vegetable matter after 

 transportation ; the other for deposition by grovpth in place. 

 The former hypothesis has had its ablest supporters in France, 

 where the close association of coal beds with transjDorted 

 deposits and the character of the coal itself lend aid to that 

 view. The latter hypothesis has been and is most favored in 

 America, England and Germany. In many cases more 

 extended studies have reduced in numbers the coal beds 

 believed to have resulted from deposition after transportation. 



The climate of coal-forming times has been a subject con- 

 cerning which ffeoloffists have held and hold different views. 

 Most that has been written on this question has sought to show 

 that a luxuriant vegetation existed at such times and that such 

 has required a warm climate for its development. From time 

 to time doubt has been cast on that view, yet it apparently 

 remains almost universally accepted at the present time. 



It is the purpose of this article to endeavor to give addi- 

 tional facts bearing on the method of deposition of the coal 

 and on the climate of past coal-forming times. The writer 

 wishes to acknowledge his obligations to Professors Charles 

 Schuchert and Joseph Barrell for advice and criticism in the 

 preparation of the paper. 



Coal beds in association with marine deposits and resting 

 directly on Jimestones of marine origin have been reported 

 from various portions of the coal fields of the United States,* 

 but to the writer's knowledge practically nothing has been 

 offered in explanation of the origin of such formations. In 

 the case described by Winslow the coal is of the cannel variety, 

 which is ordinarily assumed to have been deposited by water 

 in a quiet basin and subjected to prolonged leaching ;t but in 

 this case it lies in an erosion channel. Coal beds of this 

 character find a ready explanation, other facts being neglected, 

 by deposition after transportation. Greater difiiculty of 

 explanation arises if a continental origin by growth in place 

 be assumed. 



In the following pages sucli a coal bed now forming will 

 be described, and a brief discussion will be given of the con- 

 ditions under which it is developing. 



* 22d Ann. Eep. U. S. Geol. Surv., pp. 175, 181, 216, 1901. Winslow, 

 Arthur, Prelim. Rep. on Coal, Mo. Geol. Surv., p. 170, 1891. 

 + Dana, J. D., Manual of Geology, 4th ed., p. 710, 1895. 



Am. Jour. Sci. — Fourth Series, Vol. XXX, No. 175.— July, 1910. 

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