ss 



Report of the State Geologist. 



from the lower one because it differed "in the contained fossils, and in some 

 particulars of its lithologic character." 1 The succeeding formation — the 

 Chemung — was also named and briefly described in this report, 2 mention being 

 made of "a great variety of beautiful and characteristic fossils," several of 

 which were generically identified. 3 



Vanuxem, in 1840, reported flags of excellent quality near Sherburne, 

 Chenango count), and proposed the name Sherburne flagstones for the 

 group underlying the Ithaca, stating that, " the stones are of various grades 

 of thickness, alternating with greenish or olive colored shale," 4 and further 

 that "the flagstone mass" extended from Cayuga lake through the Third 

 Geological District."' 



Immediately following the Sherburne flagstones is the Ithaca group, 

 which Vanuxeni described as "consisting of sandstone and shales, forming a 

 thick mass, highly fossiliferous." G Next came the Chemung group, w hich 

 'forms the narrows of the Chemung river, whence its name." and finally the 

 Montrose sandstone, or sandstone of Oneonta, which, according to Vanuxem, 

 'is the last or upper rock of the Third District * * * [and | is found 

 in Otsego, Chenango and Broome counties." 7 Vanuxem also stated that the 

 Montrose sandstone covered the whole of the upper part of Susquehanna 

 county, Pennsylvania, its name being selected because it surrounds the town 

 of Montrose, in that county. Although not explained in the report of 1840, 

 the final report by Vanuxem shows that the other term, "sandstone of One- 

 onta," referred to the ledges of greenish grey sandstone on the hills near 

 Oneonta, in the southern part of Otsego county, New York. 



Professor Hall spent the field season of 1839 in western New York, 

 studying the formations of Steuben, Allegany, Cattaraugus, Livingston and 

 Genesee counties, and in his report we find a classification of the rocks of the 

 Fourth District, " giving their order of succession, together with the names of 

 a few of the most common and characteristic fossils;" the classification for 

 that part of the series which is now under consideration being as follows: 



"Old Red Sandstone. 



" Chemung Group. 



" Portage Group. 



' Third Allium! Report, Fourth Geological District, New York (Assembly Doc No. 875, 18191, p. 318. 

 » Ibid., pp. 322-324. 

 »Ibid.. p. 322. 



* Fourth AniiUHl Report, Third Geological District, New York (Assembly Doc. No. 50. 1840), p. 381. 



5 The counties forming the eastern part of the Third Geological District were Fulton, Montgomery, Otaego, Chenango and 

 Broome, which would imply that the group was regarded as reaching the eastern part of Otsego county. 

 « Fourth Animal Report, p. 381. 

 7 Ibid., p. 881. 



