Raymond : The Chazy Formation and its Fauna. 505 



exposed and abundantly fossiliferous. The final exposures are about 

 half a mile from the Beekmantown village line." 



TJic ]\ilcour Island Section. 



At Valcour Island, the Chazy is well develojied and Brainerd and 

 Seely give the following section : dip 20° to 30° eastward. 



Group A : Lower Chazy, 338 feet. 



1. Gray- or drab-colored sandstone interstratified with thin (or 

 sometimes thick) layers of slate, and with thin layers of limestone at 

 the base containing Camerella (?) costata (probably Orthis acuti- 

 plicata) . 



56 feet. 56 feet. 



2. Massive beds, made up of thin alternating layers of tough slate 

 and nodular limestone, containing undetermined species of Ortliis 2iW^ 

 Orthoceras. 



82 feet. 138 feet. 



3. Dark bluish-gray, somewhat impure limestone, in beds of variable 

 thickness, often packed with Orthis costalis Hall, which occurs with 

 more or less frequency through the whole mass. Other fossils are 

 Lingiila Jiiironensis, Eoliarpes antiqitaliis, Eoiiarpes ottawacnsis, Tlia- 

 leops ovata, Liti/itcs ?,]i. (?). 



no feet. 248 feet. 



4. Gray, tolerably pure limestone in beds 8 to 20 inches thick, sepa- 

 rated by earthy seams, the bedding being uneven. Many layers 

 consist of crinoidal fragments, largely of Falceocystites teniiiradiatus. 

 Near the middle of the mass, for a thickness of 10 feet, some of the 

 fragments and small ovoid masses (^Bolboporites aniciicaniis') are of a 

 bright red color. 



90 feet. 338 feet. 



Group B : Middle Chazy, 350 feet. 



1. Impure, nodular limestone, coxv\.2i\'Ci\XKg Maclurites mati^nus. 



25 feet. 25 feet. 



2. Gray, massive, pure limestone, abounding in crinoidal fragments. 

 20 feet. 45 feet. 



3. Bluish-black, thick-bedded limestone, usually weathering so as to 

 show pure nodular masses enveloped in a somewhat impure, light col- 

 ored matrix ; everywhere characterized by Macliirites magnus. Near 

 the middle of this mass, for a thickness of about 30 feet, the fossils are 



