13.6 Report of the State Geologist. 



s< nitheast of Swan hill, so that, making an allowance for dip, it is probable 

 that C 3 is nearer 150 than 100 feet above the base of the Ithaca formation. 



XIX C*. One mile farther east, in the southwestern corner of Colum- 

 bus, rocks are seen l>v the side of the road. This place is on top of the divide 

 between the Chenango and Unadilla rivers, from which a beautiful view of 

 the surrounding country may be obtained. These rocks are the highest of 

 this region, by the barometer 126 feet higher than C 8 , f>67 feet above the 

 Hamilton at the Nigger brook crossing, and 770 feet above the railroad in 

 Sherburne village, giving an approximate altitude of 1,812 feet A. T. They 

 consist of micaceous and arenaceous shales and shaly sandstones, part of the 

 layers containing plenty of fossils, and others scarcely any except an occasional 

 lamellibranch. The following species were collected in fifteen minutes: 



1. Spit -it'ii- mtteronatus (Con.), Bill. var. posterus, Hall and Clarke, (aa) 



These specimens in general seem to be like figures 28 and 30, 

 (plate XXXIV, Palaeontology of New York, Vol. VIII., Brachio- 

 poda II.) of this variety, although some might possibly be referred 

 to the species itself. The internal impressions in the umbona] 

 region of two or three specimens show a small groove w hich looks 

 as though they might have possessed a small septum and these 

 should be compared with Sp. mesacostalis, although I have seen 

 Sp. nmcronatus with a septum in the Hamilton (Moscow ) shales 

 of Cayuga lake. 



2. Spirt'frr i/ramdosus (Con.), Hall (?). (rr) 



Part of an external impression that show s very clearly the im- 

 pressions of pustules. 

 •">. Liorhy7ic7ius mesacostalis, Hall. (rr) 



4. Paracyclas Iwata (Con.), Hall. (rr) 



5. Nucula corbuUfdrmiSj Hall. (rr) 

 <». Palaniteilo cf. jilosa (Con.), Hall. (r) 



Impressions that do not preserve any of the surface markings 



except near the outline of the specie-. 



7. Mbdiornorpha cf. subalata (Con.), Hall, var. QTwtn/tingeTtMs, Hall, (rr) 



8. Leptodesma Rogersi, Hall (?). (r) 



9. Actmoptt via perstr talis, Hall. (rr) 

 1<>. Scli'tzorf tlx cf. dpjinssii.s (Con.), Hall. (rr) 



The upper 300 feet of this ridge, which includes the highest 

 locks of the divide, belong in the Ithaca formation. 



