348 REPORT ON THE STATE CABINET. 



Throughout the State of New York, the country along the junction 

 of the Niagara and Onondaga salt formations is low and level, or covered 

 by drift accumulations ; and no opportunity offered of discovering any 

 exposure of similar beds along the course of the outcrop. In some 

 places in Monroe county we have been able to trace the two formations 

 to within a few feet of their contact with each other ; but no fossiliferous 

 beds, similar to those of Wayne county, have been found. Subsequently, 

 after a considerable portion of Vol. ii of the Palceontohgy of New York had 

 been printed, my attention was called to some peculiar fossils collected 

 at Gait, in Canada West ; and in visiting that locality, I discovered some 

 species identical with those before known, from beds which I had regarded 

 as of the Onondaga group in New York. As this limestone at Gait 

 (and Guelph) was clearly above the great Niagara limestone of the Falls, 

 and contained an almost entirely different set of fossils, I very naturally 

 inferred that it belonged to the next higher formation, or the Onondaga 

 salt group, and that the Wayne county locality was a feeble representation 

 of the limestone of Gait.* For these reasons the two were treated as 

 identical, and referred to the age of the Onondaga salt group ; an opinion 

 at that time sustained by the members of the Canadian Geological Survey. 



At a later period, during the Geological Survey of Iowa, I recognized, 

 at the Leclaire rapids on the Mississippi River, a limestone holding the 

 same relative position, having the same lithological character, and con- 

 taining some identical and many similar fossils with the limestone of 

 Gait or Guelph, in Canada West ; and I thus announced its apparent 

 relations in the Report on the Geology of lotva, 1857, Vol. i, p. 75 : 



"Should the identity of the limestone of these two distant localities be 

 proved, it will afford sufficient ground for separating these beds from the 

 Onondaga salt group, aud for establishing a distinct group. It seems quite 

 probable that the limestones of this period have their eastern extremity in 

 Central New York, where, from their small development, as well as from 

 similarity of lithological character, there seemed no sufficient ground for 

 separating them from the non-fossiliferous beds of the Ouondaga salt group.-j- 

 Since, however, in Canada, these beds attain considerable importance, and 

 (admitting the conclusions above given) acquire a still greater thickness and 



* The name " Gait" being considered objectionable on account of a similar term already in use, 

 and the same rock occurring also at Guelph, it has been called the " Guelph formation " in the 

 nomenclature of the Geological Survey of Canada. 



t My views regarding the presence of the Onondaga salt group proper in Wisconsin and Iowa 

 have somewhere been called in question, and I have only to remark in this place that I have seen 

 no reason on my own part, nor facts adduced on the part of others, to change my opinion in 

 reference to the occurrence of this formation in the localities I have heretofore cited. 



