42 JOURNAL OF THE 



patches, while the disturbance of their orig-inal strati- 

 tjfraphic position would make it impossible to read any 

 of their history by the stratigraphy. 



If this conjecture be true, the "land barriers lying- 

 to the east " of New England would be but a part of 

 the broad pre-Cambrian land strip which extended 

 from some part of the North Atlantic in a southwest- 

 erly direction almost to the present shores of the Gulf 

 of Mexico. In such case all ideas of the Atlantic 

 shore line previous to the Triassic period are involved 

 in the statement that it existed at some distance east 

 of its f)rcsent position. 



Taking up the thread of the history at the begin- 

 ning of Mesozoic time we find a series of elongated 

 basin deposits of Triassic (Rhaetic ?) date consisting 

 chiefly of red sandstones and conglomerates. These 

 rocks form a long train of detached areas stretching- 

 from central Massachusetts southwestward to South 

 Carolina. They lie unconformably upon the denuded 

 surface of the pre-Cambrian crystallines, and appear 

 to have accumulated either in shallow inland seas or in 

 sheltered eniba3^ments of the ocean. All of them are 

 separated from the present ocean by older rocks, 

 except that of Connecticut, which itself communicates 

 with it only by a narrow neck. 



We have, then, in Triassic times very little evidence 

 of the position of the Atlantic shore-line itself. If the 

 Triassic rocks of Connecticut and New Jersey were, 

 as has been thought, deposited in embayed portions of 

 the ocean waters, or fronting the open sea, then we 

 must have had a coming in of the shore-line by sub- 

 mergence of the greater part of the pre-Cambrian land 

 area, by which the Triassic sediments accumulated 

 even upon the edges of the Paleozoic rocks of the conti- 



