Prossek — Hamilton and Chemung Skkiks. 



L93 



8. Palceoneilo constricta (Con.), Hall. (it) 



9. Liopteria DeKayi, Hall (?) (c) 



All imperfectly preserved. 



XXIV B 3 . Ledges are rather conspicuous on the hillside towards its 

 top, and 170 feet above B 2 is a prominent ledge of even-bedded, thin sand- 

 stones forming the upper terrace of the hillside. These sandstones are fine- 

 grained, greyish to slightly olive in color, weathering to a brownish grey. 

 Portions of them are literally filled with specimens of all sizes of Rhynclianella 

 venustula, Hall, although scarcely any other fossils occur; a broken specimen 

 Pa rar ijdax I) rata (Con.), Hall (?), being the only one noted. In the loose 

 fragments among the talus, apparently from this ledge, were pieces of rock 

 containing abundant specimens of Spirifer mucronatns (Con.), Bill., and a 

 single broken specimen of Palceoneilo emwginata (Con. ), Hall (?). The hill 

 is rounded above this ledge and does not extend much higher, and the rocks 

 are covered by soil; but the presence of the abundant specimens of Rhyn- 

 dhonella venustula indicates that the Hamilton formation extends nearly to its 

 summit. This ledge is 320 feet above the level of Otego creek, and when the 

 hill is compared with Mt. Vision, rather more than three-quarters of a mile to 

 the north, the highest rocks of which are 350 feet above the creek level, or 

 the top of the hill approximately 375 feet above the creek, it will be seen 

 that all of that hill must belong in the Hamilton formation, since a dip of 

 seventy-five feet per mile, probably less than the true dip, would carry the 

 Hamilton rocks over the summit of Mt. Vision. 



This Rhynchoinella venustula ledge is seven miles southeast of the locality 

 already described near Noblesville, carrying the distribution of the species so 

 much farther eastward, as well as fixing precisely in the Otego valley a point 

 for the separation of the Hamilton and Sherburne formations. 



SECTION OF THE " OWL PATCH," THREE-QUARTERS OF A MIKE SOUTH OF MT. VISION". 



320' 



150' 

 75' 



0' 



170' 



— - / 

 t o 



B 3 . Thin sandstones with abundant specimens of 

 Rhyra-lioneJla r<-/n/st xla. Top of Hamilton. 



B 2 . Coarse, arenaceous shales, abundant Hamilton 



| fossils. 



B 1 . Hamilton shales on highway. 

 Otego creek level. 



1 3 



