298 C. A. SUSSMILCH AND T. W. E. DAVID. 



The above monograph by Shaler and his colleagues and 

 that by Messrs. Sayles and La Forge, and the recent mono- 

 graph by Robert W. Sayles 1 are very instructive on this 

 subject. The Narragansett Coal Measures and the Con- 

 glomerates, possibly of Alleghany age, are considered to 

 be newer than the Pottsville Conglomerate Series (Middle 

 Carboniferous) and underlie both the Barren Measures 

 (Elk River or Conemaugh Series), and the still higher 

 Monongahela River Series; that is they lie below the top 

 of the Upper Carboniferous proper. The Narragansett 

 strata terminate upwards in massive conglomerates up to 

 2,000 feet in thickness — the Dighton and Seekonk con- 

 glomerates. If the Roxbury conglomerate of the Boston 

 area is part and parcel of the overlying "Squantum Tillite" 

 formation, as seems higlily probable, and the Roxbury con- 

 glomerate is to be correlated with the Dighton and Seekonk 

 conglomerates in the Narragansett Coal Measures, then 

 there does not appear to be any more reason why the 

 Squantum tillite should be considered Permian than Upper 

 Carboniferous. At the same time the possibility of the 

 age of the Squantum tillite being Permian is of course not 

 excluded. Nevertheless, the similarity of the contempor- 

 aneously contorted "varve" beds in the Kuttung series of 

 New South Wales to those figured by Robert Sayles is so 

 extraordinarily striking as to suggest possible contempor- 

 aneity, in spite of the fact that the Kuttung flora is more 

 Middle than Upper Carboniferous. 



(iii) Possible Glacial evidence in the Maroon Conglomerate 

 of Colorado, U.S.A. 2 



The Maroon Conglomerates of the Elk Mountains and 

 Sangre de Oristo Range of Colorado are considered to be 



1 Mem. Mus. Comp. Zool., Vol. xlvii, No. 1, Seasonal Deposition in 

 Aqueoglacial Sediments, by R. W. Saylep, Cambridge, U.S.A., Feb. 1919. 



2 Geology : Earth History. Chamberlin and Salisbury, Vol. n, p. 552. 



