538 AxxAi.s OF THE Carnec;ie Museum. 



from each zone. These fossils appear to have been lost while en route 

 to the Cornell University Museum, and op])ortunity to repeat this work 

 has not presented itself. A collection made for the Yale University 

 Museum in the summer of 1903 has supplied lists from certain of the 

 layers. These with notes made in 1902 and 1904 will serve to indi- 

 cate fairly well the nature of the fauna in the lower and middle por- 

 tion of the formation at Chazy. 



Section D, Chazy, N'etv York. 



This section begins where Tracy Brook crosses the road about a 

 mile southwest of Chazy village. 



D,. Compact, coarsely crystalline, light-gray limestone which has 

 a yellow, sandy appearance on the weathered surface. Very fossilif- 

 erous, the brachiopods being most abundant. Hebertella exfoliata is 

 common. 



These are the lowest layers at Chazy. About one eighth of a mile 

 west, beside the Delaware and Hudson railroad track, the Potsdam 

 sandstone, lying almost horizontally, is exposed. The Chazy strata 

 dip away from the Potsdam at an angle of ten to twenty degrees. 



17 feet =17 feet. 



D.^. Hard, fine-grained, dark-blue magnesian limestone, with trilo- 

 bites at the base. Species of Isotcliis and lUccnus, and many brachio- 

 pods, occur near the top. 16 feet 3 inches = 2)Z feet 3 inches. 



D3. Lithologically about the same as the preceding, but the 

 weathered surfaces show many fucoidal markings, 



19 feet 9 inches ^53 feet. 



D^. Light-gray, fine-grained dolomitic limestone with narrow but 

 conspicuous yellow streaks on the weathered surface. No fossils. 



27 feet = 80 feet. 



Dj.. Like the preceding, but with fewer yellow streaks and some 

 fossils. 9 feet 6 inches = 89 feet 6 inches. 



Dg. Concealed. 10 feet = 99 feet 6 inches. 



Top of A,, Brainerd and Seely's section. 



1).. Fine-grained, fairly pure dolomite, with the weathered surface 

 covered with cystid fragments. A^ of Brainerd and Seely's section. 



20 feet = 119 feet 6 inches. 



Dg. Concealed across a narrow trough in which there is an almost 

 stagnant stream. 40 feet = 159 feet 6 inches. 



