lOD - NEW YORK STATE MUSEUM 



One mile to the east of this section is another which shows 

 higher beds, an additional thickness of about lOO feet being ex- 

 hibited. The section is exceedingly similar to that of the upper 

 portion of the Little Falls dolomite at Saratoga, bluish gray„ 

 finely crystalline dolomite below, often with bad odor when 

 freshly broken, with many nodules of crystalline calcite, often 

 drusy, and with coarser g'rained, whitish, crystalline dolomite 

 above, with much black chert; the section capped by a massive 6 foot 

 reef of Cryptozoon, much of which is chert. This is directly 

 and unconformably overlaid by beds which seem to us to belong 

 to division C ; certainly they have the lithologic character of that 

 division. These are followed in their turn, going north, by the 

 beds of divisions D and E. 



Discussion. The bulk of this second section is mapped by 

 Brainerd and Seely as belonging to division B. They describe 

 the division as follows : 



Dove-colored limestone, intermingled with light gray dolomite^ 

 in massive beds; sometimes for a thickness of 12 to 15 feet no 

 planes of stratification are discernible. In. the lower beds, and in 

 those just above the middle, the dolomite predominates; the middle 

 and upper beds are nearly pure limestone.' 



We found no dove limestone in the section. Likely the light 

 gray dolomite is that forming the upper part of our section,, 

 though if it be, we fail to understand the lack of mention of the 

 chert which we find in it everywhere abundantly. In any case it 

 is the same horizon which Ave find everywhere to characterize 

 the summit of the Little Falls dolomite. In this section it is, as 

 we believe, in uncomformable contact with division C and thia 

 is followed by the whole of D and E, the two upper members of 

 the Champlain Beekmantown. Except where eroded away 

 during the time interval which followed, the summit of the 

 Little Falls dolomite at Ticonderoga and elsewhere is usually a 

 Cr3^ptozoon reef, often heavily charged with chert, as is the case 

 here. 



Section at Saratoga 



The Saratoga district is considerably faulted; glacial drift is 

 widespread and often heavy, and a complete, detailed section 

 can not be made out from study of the surface outcrops. The 

 Mohawkian rocks rest on an uneven, eroded surface of the dolo- 

 mite group,, varying beds of each group being at the contact in 

 the different exposures. The general section is as follows : 



^Op. cit. p. 2. 



