XIV. THE PELECYPODA OF THE CHx'\ZY FORMATION. 

 By Percy E. Raymond. 



The present paper is the eighth, and probably the last, of a series 

 of papers in which the writer has dealt with the fauna of the Chazy 

 formation of New York, Vermont, and Ontario. Six of these papers 

 are published in these Annals, the first being entitled, "The Trilobites 

 of the Chazy Limestone, "^ and the others, in order, "The Chazy 

 Formation and its Fauna,"" "The Gastropoda of the Chazy Forma- 

 tion,"^ "New and Old Trilobites from the Chazy,"* and "The Brachio- 

 poda and Ostracoda of the Chazy. "^ The present paper is the sixth. 



The two papers not published in the Annals contain little which 

 is not given in the above papers. The first, "The Fauna of the Chazy 

 Limestone,"^ contained a summary of the results of the study pub- 

 lished in the Annals as "The Chazy Formation and its Fauna." 

 The other paper, "The Trilobites of the Chazy in Vermont,"' is a 

 revised and corrected compilation of the two papers on Chazy trilobites 

 published in these Annals, and contains all the plates of both papers. 



Since the writer began publishing on this fauna, two authors have 

 made valuable contributions to our knowledge of the fossils of the 

 Chazy. Dr. Ruedemann has published an extremely good account 

 of the Cephalopoda^ and Professor Hudson, in several articles, has 

 dealt extensively and in detail with the Echinoderms. Professor 

 Hudson's persevering work on the decomposed material in the fault 

 on Valcour Island has been rewarded by the discovery of a great 

 variety of very interesting specimens, and his remarkable genius for 

 detail has enabled him to derive a great amount of information from 

 his spoils. His most remarkable find was the nearly complete speci- 



1 Annals Carnegie Museum, Vol. Ill, 1905. 



''Vol. Ill, 1906. 



3 Vol. IV, 1908. 



< Vol. VII, 1910. 



6 Vol. VII, 1911. 



^American Journal of Science, Vol. XX, 1905. 



' Seventh Report Vermont State Geologist, 1910. 



8 Bull. 90, N. Y. State Museum, 1906, pp. 393-528, Pis. 1-38. 



325 



