SPIRIFER^E OF THE CHEMUNG GROUP. 



24r 



very rarely narrow and angular, as shown in fig. 17. The casts usually preserve 

 more or less distinctly the marks of the plications, and are rarely almost smooth. 

 The following figures are those which were given in the Geological Eeport of 

 the Fourth District, and have not been repeated in the plates. They oflTer some 

 little variety of form and proportions from those already referred to.* 



Geological formation and localities. This species occurs in the Chemung group 

 throughout New- York, and in that part of Pennsylvania adjacent to the south- 

 western counties of this State. Among the particular localities may be mentioned 

 several places in Broome county; Cayuta creek in Tompkins and Tioga counties; 

 Factoryville, Chemung-uarrows, Chemung, Paintedpost and Elmira, in Chemung 

 county; near Angelica, Vandemark's creek, Olean, and other places in Allegany 

 county; Troupsburgh, near Bath, and elsewhere in Steuben county; at Sala- 

 manca, Allegany station, New-Albion, Napoli, Randolph, Connewango, Great- 

 valley, Leon, etc. in Cattaraugus county; at Ellington,, Twenty-mile creek, and 

 other places in Chautauque county. 



In Pennsylvania, I have collected this species from Covington and localities 

 to the north of Blossburg, and Mr. R. P. Stevens has sent me specimens from near 

 Bradford. It is abundant at Meadville and vicinity. 



• The illustrations in wood cuts were given in the Geological Report of the 4th District as 1 Dd- 

 tkyrit cuspidata, 2 and 2a; D. acarUhota, 4 and 4a; D. inermis. 



