180 



Repokt of the State Geologist. 



New Lisbon. 



XX IP. In the northwestern part of the township, one and one-half 

 miles northwest of Garrattsville, is a small glacial lake known as Turtle lake. 

 The ground is marshy about the lake, but along its outlet and in a small run 

 which enters the l>rook from the south are rocky ledges. The arenaceous 

 shales on the outlet of Turtle lake are apparently in the Hamilton formation, 

 fossils being common, as the following list will show: 



1. 



Uropidoleptus carinatus (Con.), Hall. 



(a) 







Spirifer mucronatus (Con.), Bill. 



(IT) 



3. 



Spirifer granulosus (Con.), Hall. 



(IT) 



4. 



Spirifer Tullius, Hall. 



(IT) 



5. 



Cyrtina Haniiltonensis, Hall. 



(IT) 



6. 



MicroiJon (( ^ijprico nJeJJa) fen iiist riot tis, Hall. 



(it) 



7. 



Microdon (Cypricardella) bellistriatus, Hall. 



(rr) 



It 



is somewhat difficult to determine sharply the 



line between the Hamil- 



ton and Sherburne on this hill. Shales or thin sandstones containing but a 

 few fossils continue for forty feet up the small run southwest of the main 

 creek. A few of the Hamilton species in this locality seem to occur somewhat 

 above the horizon of the top of the Hamilton, in shales which, farther west, 

 are in the lower part of the Sherburne. 



AX IP. Sixty-five feet above the outlet of Turtle lake, greenish shales 

 and sandstones begin and continue for fifty feet to the top of the hill. These 

 rocks contain a few fossils; thirteen specimens of IAorhynchus mesacostalis, 

 Hall, and two of Spirifer mucronatus (Con.), Bill., were collected beside speci- 

 mens having fucoidal markings. These fifty or more feet of shales and sand- 

 stones are regarded as belonging in the Sherburne formation, but it appears 

 that the unfossiliferous tine blue shales of the Unadilla valley have changed 

 into these more arenaceous shales in which Liorhunchus is not uncommon. 

 In the brook to the west of Turtle lake and near the divide, are smooth rocks 

 w hich may belong in the Hamilton, while the loose ones on the ground are 

 very similar to the Sherburne. The elevation of this locality is about the 

 same as the horizon considered as the top of the Hamilton south of Turtle 

 lake, but on account of the heavy deposit of drift over the region of the 

 divide, it is difficult to determine accurately the underlying geologic for- 

 mation. 



XX IP. Ledges near the upper part of the glen, one-half mile north- 

 west of Garrattsville and 120 feet higher than the village hotel. The rocks 



