Raymond : The Chazv Formation and its Fauna. 573 



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specifically identified, and of these 30 per cent, are Mohawkian 

 species. 



The lowest member of the Stones River Group is the Murfreesboro 

 limestone, which is about 60 feet thick and contains 24 species, 21 of 

 which are identified. The fauna is comi)osed principally of mollusca, 

 gastropods of the genera LopJiospira and Liospira being particularly 

 abundant. Of the 21 species, 11 are Black River or Trenton, so that 

 52 per cent of the species of this oldest member of the Stones River 

 Group belong to the Mohawkian. 



Thus, of the 58 described species occurring in these four divisions 

 of the Stones River Group, 27, that is, 46 per cent., occur in the 

 Mohawkian." Comparing this large percentage of forms common to 

 the Stones River and the Black River and Trenton, with the low per- 

 centage, less than 5 per cent., of forms common to the Chazy and 

 Mohawkian, it becomes evident that the Stones River and Trenton 

 faunas are much more closely connected than are the Chazy and Tren- 

 ton faunas. This close relationship, faunally, of the Stones River 

 and Trenton, coupled with stratigraphy, suggests that the whole 

 Stones River is younger than the Chazy. 



The Blue Limestone of Lenoir s^ Tennessee. — The Mac In re a lime- 

 stone of East Tennessee was correlated by Safford with the Chazy or 

 Black River of New York and Canada, and Ulrich and Schuchert 

 have held that the deposits of their Lenoir Basin were made during 

 Chazy time. A section at Lenoirs afforded the writer a small fauna 

 containing fossils characteristic of Division 2 in the Lake Champlain 

 region, and it is possible that the typical Chazy fauna may exist at 

 Lenoirs, but the region needs further study before definite correlation 

 is made. 



Relation of Divisions i, 2, and 3, to Cushing's Suhstages. 



In a recent article (Bulletin New York State Museum, number 95) 

 Professor Cushing has proposed names for the three divisions of the 

 Chazy as limited by Brainerd and Seely. Their basal division. A, is 

 called the Day Point limestone, division B, the Crown Point lime- 

 stone, and C, the Valcour limestone. These divisions are proposed 

 because they are "sharply marked off from each other lithologically 



^' Of course these percentages will be modified when the whole Stones River 

 fauna is known. As the Stones River and Chazy faunas occupy difi'erent basins, 

 positive correlations cannot be drawn by this tncthod. 



