SIXTH REPORT OF THE DIRECTOR I909 I27 



Feet Inches 



10 Brittle, cove limestone, of ordinary Lovvville char- 

 acter, full of Phytopsis tubes 13 



9 Brittle, dove limestone, with occasional sand grains 

 in the basal layer; slightly impure as shown by 

 irregular laminations on weathered surfaces; 

 T e t r a d i u m c e 1 1 u 1 o s u m occurs below 



summit 6 ^ 



8 Concealed except for the surface of one layer at 

 base, which is slightly impure dove limestone, with 



frequent sand grains i 9 



7 Concealed 3 



6 Thin bedded, light colored sandy limestone and cal- 

 careous sandstone ; shaly partings ; probable base 



of Lowville 4 6 



Hiatus and unconformity 



5 Concealed 20 



4 Massive, gray, drusy dolomite; quartz sand grains. . i 6 



3 Irregular, massive to thin bedded, sandy, gray dolo- 

 mite; many druses above; many sand grains ; cer- 

 tain layers mottled and laminated with black. ... 13 



2 Concealed 15 



I [Massive, granular, blue gray dolomite, but few. sand 

 grains ; Cryptozoon and much chert in lower 5 

 feet 8 



Here we find the Lowville thickness to exceed 28 feet, as against 

 the 15 feet shown in the Middleville section; we have also beds 

 intervening between the Lowville and the Trenton which do not 

 appear in the Middleville section. But as in that we find no trace 

 of the Tribes Hill formation, the Lowville resting on the Little 

 Falls dolomite. 



In these western sections of the Little Falls dolomite, we miss 

 the light colored, coarsely crystalline beds which form the sum- 

 mit of the formation at the east. Whether they were deposited 

 and eroded before the deposition of the Tribes Hill, or whether 

 they change laterally into finer grained, gray beds on passing west, 

 we are not sure. Since the formation shows no diminution in 

 thickness it is perhaps more probable that the latter is the case. 



Theresa formation 



This name was given by Cushing two years ago to the passage 

 beds and overl\ing magnesian limestones which occur between the 



