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NEW YORK STATE MUSEUM 



this region must however be considered. 1 These two examples 

 represent overlaps on the eastern shore of the central Helder- 

 bergian sea (Cumberland channel). 2 



In the northern region a good example of overlap is seen in 

 the Helderberg outlier of St Helen's island in the St Lawrence 

 river, opposite Montreal. 3 Here a limestone with upper Helder- 

 bergian (Becraft-Port Ewen) fossils rests directly on the Utica 

 beds. The fauna of this limestone is in part suggestive of the 

 Oriskanv, thus showing these beds to be very late HelderbergTian. 

 This overlap marks the neighborhood of the western shore of 

 the Helderberg sea in that region. Schuchert thinks that " there 

 is no clear evidence that the Albany county, X. Y., area ever 

 connected with Montreal by way of the Champlain valley, as 

 was supposed by Logan and Dana to be the case." 4 No real 

 reason is known to me why these areas need be considered dis- 

 tinct, since the Champlain region has been peneplained down to 

 the Champlainic, and any Helderbergian beds formerly existing 

 here would be removed by erosion. The similarity between the 

 St Helen's Island, and New York Helderberg faunas suggests 

 a direct connection; the elements of difference between these 

 faunas indicate that the connection was by a narrow channel. 



The fauna of the Square lake limestone of Aroostook county. 

 Me. 5 suggests a relationship with the upper beds of the Helder- 

 bergian of the New York areas. However, several species un- 

 known in the New York Helderberg are found here, and link 

 the fauna more closely with that of Gaspe. Whether the fauna) 

 difference is such as to require placing this eastern fauna in a 

 separate basin, or whether the difference of the faunas is to be 



1 See Ries, N. Y. State Geol. 15th An Rep't, p. 427. I am indebted to Mr 

 C. A. Hartnagel for calling my attention to this and the preceding occurrence. 



2 The .Rensselaer grit of eastern New York may represent the over- 

 lapping clastic margin of the Helderberg rocks resting on upturned and 

 eroded Cambric and Champlainic hods. 



3 Schuchert. Am. Geol. 1901. 27:245. 



1 More recently Professor Schuchert has expressed the helief in a channel 

 in the Connecticut valley region (Private letter). 



*See Billings. Portland Sue. Nat. Hist. Proc. v. 1. '18C3 ^Williams, H. S. 

 U. S. Geol. Sur. Bui. 105. 



