XX. THE CHAZY FORMATION AND ITS FAUNA,' 

 Rv Percy E. Raymond. 



Introduction. 



As long ago as 1847 Professor James Hall stated : "I think there 

 is scarcely another portion of our series that offers a better field for a 

 paleontologist than the lower limestones, which are so well developed 

 along the valley of Lake Champlain, the Mohawk ^'alley, and the 

 Black River " (" Paleontology of New York," Volume r). 



Despite this promising suggestion, for sixty years the field has lain 

 almost neglected, as practically nothing has been added during that 

 time to our knowledge of the Chazy faunas in New York. 



From the Canadian outcrops of these same beds Billings in 1858 

 to 1865 described many nevv species, but very few, if any, of these 

 have even been noted in the New York and Vermont areas. 



During their stratigraphic work in the Champlain Yalley Brainerd 

 and Seely collected many fossils from the Beekmantown and Chazy 

 strata, and Whitfield described many new species from their collec- 

 tions. Practically all of these were, however, from the Beekman- 

 town, so that there have been only two or three species added to the 

 Chazy fauna since the publication of Billings' last paper on the sub- 

 ject in 1S65. Recently (April, 1905), an article by Professor Hud- 

 son of Plattsburgh has appeared, in which several interesting new 

 species are described. 



Upon taking up the work the original intention of the writer was 

 to study the faunas of the Chazy formation in regard to their associ- 

 ation, range, and distribution, but after a little study of the collections 

 made for that purpose it was found that there were many unknown 

 species, and that there was much uncertainty about many of the de- 

 scribed species, so that identification of the material was impossible. 



' This article is one of a series on the Chazy formation and its fauna. The first, 

 entitled "The Trilobites of the Chazy Limestone," appeared in the Annals of this 

 Museum in March, 1905. The other articles will appear in successive numbers of 

 the Annals. .\n abstract of this article appeared in the American Journal of 

 Science and Arts \\\ November, 1905. 



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