44 NEW YORK STATE MUSEUM 



more angular and lacks the distinct folds on either side of the sinus. In 

 these features, differential from S p. bicostatus, it agrees with a large 

 form which is described and figured by Hall from the Coralline limestone 

 as"Spirifer s p." ' and is stated to be closely allied to Sp. crispus but 

 differing in size. This agreement extends even to four of the five very low 

 costae observed on the casts from the Coralline limestone of Schoharie. 

 The form from the Guelph dolomite [see plate 4, fig. 21, 22] unites the 

 characters of Sp. bicostatus with this unnamed Spirifer. S p. bico- 

 status in New York is only known from its original locality, Vernon 

 Center in Oneida county, in the eastern extension of the Lockport lime- 

 stone. It seems, therefore, probable that this group of forms is restricted 

 to the Guelph dolomite, the eastern extension of the Lockport limestone 

 in the center of the State, where the stratigraphic relations are not fully 

 known, and to the Coralline limestone. 



Whiteaves' states that the characters of two ventral valves from 

 the Guelph at Durham Ont. are so similar to those of Sp. bicostatus, 

 as described and figured by Hall, that it is possible these should be referred 

 to that species rather than to Sp. plica tell us. This species and its 

 variety, r a d i a t u s, replace Spirifer crispus in the western Racine 

 and Guelph beds, from which the latter has not been reported. 



whitfikluklla Hall & Clarke. 1892 

 Whitfieldella nitida Hall 



Plate 4, fig. 31-37 



Atrypa nitida Hall, Geology of New York; rep't on fourth dist. 1843. table 

 of organic remains 13, fig. 5 



This is the most common brachiopod in the higher horizon of the 

 Guelph dolomite at Shelby and at Rochester. Most of the examples are 

 relatively small, in this feature approaching more nearly the New York 

 Niagaran than the Waldron, Indiana, specimens. One exhibits lateral 

 folds, an occurrence at times observable in the Waldron shell. 



'Pal. N. Y. 2: 327, pi. 74, fig. 7, 8a-d. 

 'Paleozoic Fossils, v. 3, pt 2, p. 62. 



