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NEW YORK ST. VIE MUSEUM 



Formations and localities. Hall, in the original description, states: 

 "This species is among the most common in the slates near Albany, and at 

 Ballston, Saratoga co. It is more rarely seen in the slate in Columbia 

 count)', and its occurrence in the Mohawk valley doubtful. It occurs like- 

 wise at Cincinnati and other western localities and appears to be the most 

 common species in that part of the country." Walcott, the next author in 

 this country who mentions it, cites it as occurring in the Utica shale (includ- 

 ing Normanskill shale) and in the Hudson River (Lorraine) shale. We 

 now know that it is one of the most common forms of the Normanskill 

 shale throughout the New York slate belt, and extends with this forma- 

 tion into the provinces of Quebec and New Brunswick and probably 

 equally far southward into the Appalachian trough though it is not yet 

 recorded south of the State of New York and collections from New Jersey 

 and Alabama have failed to show it. The species persists through the next 

 zone (according to Lapworth in neighborhood of Quebec and according to 

 Gurley at Magog, Canada) and into the Utica shale of the Mohawk valley, 

 whence it has been first recorded by Whitfield. According to the writer's 

 observations it is there represented only by a smaller mutation and of rare 

 occurrence (Dolgeville). In the Utica shale of the Hudson river region 

 this mutation has been only once observed by the writer. It apparently 

 occurred farther south in the Appalachian trough, for a specimen of the 

 same mutation has been noticed in a small collection from Strasburg, Ya. 



This species, or any mutation of it, has not been traced in-this State into 

 the Lorraine beds. From Hall's statement that it is the most common 

 species at Cincinnati and other western localities, one might conclude that it 

 must be a common Lorraine or Richmond form, but I have failed to find it in 

 the Ulrich collection of graptolites from the Ohio basin, nor is it mentioned 

 by Winchell and Ulrich in the fossil lists of the Champlainic deposits of 

 the Upper Mississippi province [Geol. Min. v. 3, pt 2] or cited by Gurley 

 in his synoptic list of graptolites [Jour. Geol. [896] from the Cincinnati, 

 Maquoketa and Lorraine shales. It is also absent in a collection ol Maquo- 

 keta graptolites sent to me by Professor Sardeson. There is hence fair 



