390 PALEONTOLOGY OF NEW YORK. 



TROCHOCERAS, Barrande-Hall. 



The genus Trochoceras was proposed by M. Barrande and by myself, about 

 the same time, and quite independently of each other, for fossils of identical 

 character and structure. The name was first published by M. Barrande — 

 my own appearing only in the second volume of the Palaeontology of N. Y., 

 Recognizing these facts, M. Barrande has done me the honor to associate 

 my name with his own in his subsequent publications of the genus, and I have 

 adopted the same course. 



In 1852 J. Hall described Trochoceras Gebhardi and T. turbinatum, from the 

 Coralline limestone of the Niagara group {Paleontology of New York, vol. 2). 



In 1800 Mr. J. H. McChesney described T. Desplainense, from the Niagara 

 group (New Palaeozoic Fossils). 



In 1801 J. Hall described T. Clio and T. eugenium, from the Schoharie grit 

 (Fourteenth Rep. N. Y. State Cab. Nat. Hist.); T. costatum, from the Niagara group 

 of Wisconsin (Geolog. Survey of Wis.: Rep. of Progress) ; and T. discoideum, from 

 the Schoharie grit (Desc. New Species Foss.). 



In 1805 Messrs. Meek and Worthen described T. Bceri [=Nautilus], from the 

 Hudson-river group (Proc. Acad. Nat. Sci. Phila.). 



Messrs. Winchell and Marct described Gyroceras Bannisteri [= Trochoceras] , 

 from the Niagara group of Illinois. 



In 1807 J. Hall described T. notum, from the Niagara group of Illinois 

 (Twentieth Rep. N. Y. Stale Cab. Nat. Hist.). 



In 1809 M. Barrande described T. incipiens, from the Quebec group (Syst. 

 Sil. du centre de la Boheme). 



In 1870 J. Hall described T. Apneas, from the Niagara group of Iowa 

 (Twentieth Rep. N. Y. State Cab. Nat. Hist.: Revised ed., explanation of pi. 25). 



In 1870 J. Hall illustrated T obliquatum, T. Pandion, Cyrtoceras Orion [=T. 

 Orion], from the Schoharie grit (Illustrations of Devonian Fossils); and T. Wal- 

 dronense, from the Niagara group of Indiana (Twenty-eighth Rep. N. Y. State Mus. 

 Nat. Hist.). 



