SPIRIFERJE OF THE CHEMUNG GROUP. 
very rarely narrow and angular, as shown in fig. 17. The easts 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 Report of 
the Fourth District, and have not been repeated in the plates. They offer 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, Cheipung-narrows, Chemung, Paintedpost and Elmira, in Chemung 
county; near Angelica, Van demark’s creek, Clean, 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- 
thyris cuspidata, 2 and 2a; D. acanthota, 4 and 4a; D. inermis. 
