P. F. Raymond — Fauna of the Chazy Limestone. 353 



Art. XXXYIII. — The Fauna of the Chazy Limestone ;* by 

 Percy E. Raymond. 



Introduction. 



In severa] papers on the Chazy limestone, Brainerd and 

 Seely have given sections showing the lithological characters 

 and thickness of the rocks at various localities from Chazy, 

 New York, south to Orwell, Vermontf These authors have 

 divided the formation into three parts, A, B, and C, of which 

 A is the base and C the top. These divisions are founded 

 partly on lithologic and partly on paleontologic grounds. Only 

 a few species of fossils, however, were listed ; hence it has 

 been the object of the present writer to ascertain which are 

 the common species in the Chazy, and to learn their strati- 

 graphic and geographic distribution. For this purpose, 

 detailed sections have been made at Crown Point, Valcour 

 Island, and Chazy, and extensive collections have been obtained 

 at other places in the Champlain and Ottawa valleys. The 

 sections will be fully described in the Annals of the Carnegie 

 Museum. In this place, however, only a synopsis of each is 

 given. 



Distribution. 



The Chazy formation w r as named by Ebenezer EmmonsJ 

 from the outcrops studied by him at Chazy village, New York, 

 this locality, therefore, becoming the typical one for the 

 formation. 



In stratigraphic position, the Chazy overlies the Beekman- 

 town (Calciferous) and underlies the Lowville (Birdseye) 

 member of the Mohawkian. It may be traced from Orwell, 

 Vermont (along the Champlain Yalley), to Joliette, north of 

 Montreal, Canada. In the Ottawa Yalley, it extends from 

 Hawksbury west to Allumette Island, 80 miles northwest of 

 Ottawa. The formation is seen again at the Mingan Islands 

 in the St. Lawrence, where it covers a small area. 



In the Lake Champlain region, these strata are mostly lime- 

 stone, and the thickness ranges from 60 feet at Orwell to 890 



* Abstract of part of a thesis presented to the Faculty of the Yale Uni- 

 versity Graduate School for the degree of Doctor of Philosophy. The 

 detailed paper, with full discussion and illustration of species, will be pub- 

 lished in early numbers of the Annals of the Carnegie Museum. For descrip- 

 tion of the trilobites here mentioned, see Annals of the Carnegie Museum, 

 vol. iii, p. 3.28, and this Journal, vol. xix, p. 377. Other new forms noted in 

 the text are described at the end of the present paper. 



f Amer. Geol., vol. ii, p. 323, 1888; Bull. Geol. Soc. Amer., vol. ii, p. 

 300, 1891 ; Bull. Amer. Mus. Nat. Hist., vol. viii, p. 305, 1896. 



% Geology of New York, Pt. 2, Eeport of the Second District, 1842, p. 107. 



