SIXTH REPORT OF THE DIRECTOR I909 IO3 



valleys and seems to us also to show that the Little Falls dolo- 

 mite (Division A and the lower part of B) does not properly 

 belong with the Beekmantown, either structurally or faunally, 

 and has been heretofore classed with it simply on the basis of 

 supposed lithologic resemblance ; that it is separated from the 

 remainder of, or rather the true Beekmantown, by an uncon- 

 formity, while it invariably grades into the Potsdam beneath 

 through a series of passage beds ; and that faunally also its asso- 

 ciation is with the Potsdam, the Hoyt limestone of the Saratogan 

 region being merely a more calcareous and more fossiliferous 

 phase of its lower portion, of very local character, rather than a 

 phase of the Potsdam. 



Detailed sections 

 Commencing at Ticonderoga on Lake Champlain the sections 

 will be given in order, passing to Whitehall, 20 miles south of 

 Ticonderoga; to Saratoga, 35 miles farther and south-southwest 

 from Whitehall; to Cranesville in the Mohawk valley, 20 miles 

 southwest of Saratoga ; and then west through the valley to 

 Little Falls, Middleville and Newport, 35 to 45 miles away. 



Section at Ticonderoga 



Brainerd and Seely have mapped and discussed the Beekman- 

 town section in the vicinity of Ticonderoga. It is but a few 

 miles west of their type locality at Shoreham, and they map all 

 five of their subdivisions of the formation. It may thus be re- 

 garded as giving a quite typical representation of the Beekman- 

 town section of the Champlain valley. 1 



Since our purpose was a detailed comparison of a portion of 

 the section with sections elsewhere, we made no effort to study 

 the whole in detail. Potsdam sandstone is exposed in the creek 

 through the village, and commencing 60 feet above the creek 

 level we measured the following section up the hill to the north, 

 known as Mount Hope, the 60 foot gap probably consisting 

 partly of Potsdam and partly of passage beds : 



SECTION JUST NORTH OF TICONDEROGA 



34 Light gray, finely crystalline limestone, to top of 



exposure 1 



33 Gray, calcareous sandstone 7 



'Am. Mus. Nat. Hist. Bui. 3:10-14. 



Feet Inches" 



