76 PALEONTOLOGY OF NEW YORK. 



should these differences prove of generic importance, I propose for them the 

 name Meristella." In the report for the following year (pp. 74, 75, published 

 in 1860), the name wiis formally defined, and the distinction of the group from 

 Merista was based upon the absence of the shoe-lifter process. Much of the 

 discussion in this place involved comparisons with the Atrypa tumida of Dalman, 

 and as no type-species was definitely cited, some authors have regarded the 

 Swedish species as the type of Meristella. Such, however, was not the inten- 

 tion of the argument, and it was definitely so stated in a subsequent paper.* 

 Athrypa tumida had been placed by Mr. Davidson, first in a list of the typical 

 representatives of the genus Merista,! *nd opportunity was taken in this place 

 of demonstrating its similarity to SuESs's type, M. herculea, Barrande, but with- 

 out the expression of an opinion as to its homogeneity with the species there 

 cited in the list of examples of Meristella, viz.: "Meristella lavis, M. bella and 

 M. arcuata, of the Lower Helderberg group ; M. cylindrica and M. oblata, of the 

 Niagara and Clinton groups." 



In the printing of the Thirteenth Report some changes were made in the 

 matter relating to this genus after a very few of the pages had been struck off. 

 As some of these first impressions fell into the hands of certain authors and 

 elicited some degree of criticism, it seemed desirable to reproduce these pages 

 in their original condition. This was done in the Fifteenth Annual Report of 

 the New York State Cabinet of Natural History (pp. 178-181). In this place 

 Meristella was erroneously made synonymous with Liorhtnchus, the types 

 quoted being Atrypa quadricosta, and A. multicosta, of the Hamilton group. This 

 publication is void, and is referred to here only because of its having unfortu- 

 nately introduced an element of confusion into the literature of this genus. 



In the fourth volume of the Palaeontology of New York (1867, pp. 295-299), 

 Meristella was more elaborately described and the complicated structure of 

 the loop demonstrated and illustrated from silicified specimens of M. arcuata. 

 The statement is there made, and has been subsequently confirmed, that the 

 structure of this organ in Meristella lavis, which was the type-species in the 

 description of 1860, is the same as that in M. arcuata. 



'Twentieth Rept. State Cabinet (1867) : On the Genera Athyris, Merista and Meristella, p. 264. 

 t Introdaction to British Fossil Brachiopoda, p. 87. 



