GUELPH FAUNA IN THE STATE OF NEW YORK 9 



of the Rochester shale and Lockport limestone. The paper concluded with 

 a list of 15 species identified by the author as common to the Canadian 

 and Rochester Guelph. 



It would be impracticable for any investigator to obtain access to these 

 species except by such personal consideration as that shown us by Mr Arey 

 who has availed himself of transitory opportunities not likely to return. As 

 the Nellis quarry is no longer productive, and the student can hardly wait 

 for possible further city excavations into this interesting horizon, we have 

 endeavored, with the important Arey collection as a nucleus, to further 

 exploit this interesting fauna throughout western New York. 



The natural sections of the dolomite series in Monroe county are very 

 few, incomplete and unsatisfying. To the series of sections made as a 

 result of searching all the water courses and trenchings, we shall presently 

 refer ; as none of them expose the strata with which we are now con- 

 cerned, we can correlate them most satisfactorily after consideration of 

 the developments given in the following. 



Section of the dolomites at Shelby, Orleans county 



While zigzagging across the Niagara cuesta in 1901 in the search for 

 this Guelph horizon, the writers discovered a finely extended outcrop of the 

 dolomite series along Oak Orchard creek, from i to i^ miles south of 

 Shelby village, in Shelby, the southwestern township of Orleans county. 

 Oak Orchard creek, a few miles to the south of this place, receives the Erie 

 canal feeder or drainage channel from Oak Orchard swamp, and from that 

 point the artificial and natural water courses are combined. To effect 

 this function, the bed of the creek has been depressed by excavation of the 

 natural rock section to a depth of 8 to 10 feet, and an immense amount of 

 material thrown on the banks in most favorable situation for examination. 

 The stratigraphic section here stretches along the creek for about 2 

 miles, and has been briefly sketched in a previous publication. 1 

 At the base of the falls at Shelby are 



1 N. Y. State Paleontol. Rep't 1901, p. 521. 



