Prosser — Hamilton and Chemung Series. 



the Hamilton on the hill south of Turtle hike to the level of the hiarh- 

 way at Stetsonville. On the hillside, one mile below Stetsonville, and 

 three miles northeast of Morris, are even-bedded, thin sandstones and 

 arenaceous shales, in which no fossils were found belonging to the Sherburne 

 formation. 



One hundred feet higher, or 21<> feet above the highway are shaly, 

 arenaceous rocks (XX G 1 ) that contain abundant specimens of Atrypa retic- 

 ularis (Linne), Dal, and a few other fossils. This ledge is probably in the 

 lower part of the Ithaca formation. Below are more even-layered shales, with 

 an occasional fossil similar to those in the more arenaceous portions of the 

 Sherburne. The fauna of G 1 is : 



1 . Atrypa reticularis (Linne), Dal. (a) 



Rather small and gibbous specimens. 



2. C'/tonetes, sp. (rr) 

 Echmocaris cf. punctata, (Hall), Whitfield. (rr) 



Part of the impression of the cephalo thorax whose surface 

 markings resemble those of this species. 



XXI B 1 . East of the Butternut Creek, and directly east of Noblesville, 

 near the foot of the hill, are quite smooth, greenish sandstones, in the midst 

 of which are blocky shales in which ffli yn< -lion ell «, ceii.usftda,H&]l, is common. 

 A few other species are associated with the JRhynchonella, but they occur 

 sparingly. Below this horizon are bluish shales which were shown in an 

 excavation for a well, while higher on the hillside, along a small run, are thin, 

 arenaceous shales, evidently the Sherburne formation, in which fossils w ere 

 not found. The fauna of B 1 is : 



1. Spvrifer mucronatus (Con.), Bill. (rr) 



2. Atrypa reticularis (Linne.), Dal. N (r) 



The rather small form. 



3. Tropidoleptus carinatus (Con.), Hall. (rr) 



4. Rhynchonella (Hypothyris) venustula, Hall. (c) 



While engaged in the field work necessary for determining th^ t<>p of the 

 Hamilton formation in the Butternut valley, the line of separation between 

 the Hamilton and Sherburne formations was indicated as approximately the 

 same horizon as that at which Rliynclionelhi eemistida was found. Later, 

 the specimens were carefully compared with the figures of this species and 

 authentic specimens from the State Museum, and it w as found that in form. 



