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region and on the rock shelves bordering the river. They are well 

 known to the populace as " fish bones " which they indeed 

 much resemble when broken through the middle. Also two species 

 of large Endoceras, distinguished by Hall as Endoceras 

 1 o n g i s s i m u m and E. multitubulatum are frequently 

 seen to attain several feet in length and half a foot in diameter. 

 Gonioceras a n c e p s, readily recognized by its lyre-shaped 

 septa, is rarer and Lituites undatus, another of the char- 

 acteristic cephalopods of the formation is also less frequently 

 observed. There is also a fairly large fauna of brachiopods and gas- 

 tropods present, which, however, has been generally lost sight of 

 since the fossils are hard of extraction in the massive rock and 

 inconspicuous in comparison with the large cephalopods. This 

 smaller fauna has not yet been described. 



Physiographically the Leray and Watertown limestones form by 

 far the most striking feature of the region. Their massiveness and 

 hardness as compared with both the underlying typical Lowville 

 limestone and the overlying shaly Trenton beds cause them to form 

 a distinct plateau or terrace, rising with a frequently vertical escarp- 

 ment from the Lowville exposure. This escarpment, however, does 

 not present the straight face of the Helderberg cuesta but is deeply 

 indented or composed of many parallel ridges separated by about 

 equally wide valleys, and stretching in fingerlike groups for miles 

 upon the Lowville plain. These fingers are especially well seen on 

 the map northeast of Limerick, and west of Perch river. They rise 

 abruptly from the Lowville plain while the intervales rise more 

 gradually to the level of the Watertown limestone plateau. The di- 

 rection and form of these fingerlike erosion ridges and their rela- 

 tion to the prevalent direction of jointing in each special case sug- 

 gest that they originated from ice plucking between especially deep 

 and wide joints. 



The Watertown limestone plateau is in comparison to the small 

 thickness of the formation abnormally wide and the Watertown belt 

 correspondingly broad on the geological map. This is due to the 

 fact that the Trenton rocks are little compact and were easily swept 

 off the massive Seven foot tier by the ice. The latter forms thus the 

 surface rock over a very large area and is in many places swept clear 

 of soil. This fact and the many deep joints make it a very poor 

 underground for agricultural purposes, and the plateau is there- 

 fore frequently wooded, especially so the jagged and deeply jointed 

 boundary region along the Lowville belt. Even small brooks have 

 frequently formed deep solution and erosion ravines in this forma- 



