Raymond : The Chazv Formation and its Fauna. 595 



separated the two channels, up the St. Lawrence to the northeast angle of 

 the Adirondack mass, where it divided, one arm entering the Ottawa basin, 

 the other passing on up the Champlain Valley to or about Westhaven. The 

 typical Chazy formation, which represents the deposits of this bay, l)ei.rs 

 evidence in its members of having encroached southward and westward in 

 its arms, the latest beds, except where, apparently, they were removed 

 before being covered by the next formation, extending farthest south and 

 west. 



1903. -SiiiMKK, IIervey W. Columbia University Geological Department — Ac- 



count of Summer Field \\'ork — American Geologist, Vol. 32, p. 130. 



In describing the formations to be seen at Larrabee's Point, Mr. Shimer 

 says : 



"Upon the Beekmantown rests the Chazy, a dark, heavy-bedded lime- 

 stone forty to fifty feet thick. This contains many fossils, the most char- 

 acteristic of which is 3/ac/urta tiiagnr. The rock also contains very many 

 O)ilioceras and Cyrtoceras shells." 



1904. Perkins, George H. The Geology of Grand Isle County. Report of the 



Vermont State Geologist, New Series, Vol. 4, p. 103. 



In this report the Chazy outcrops of the whole of Grand Isle County are 

 described. The most important part is the detailed description of the for- 

 mation as it occurs at Isle La Motte. On this island the lower and middle 

 beds are well exposed, while the upper part of the formation is covered Ijy 

 a marsh. On the south end of the island the contact of the Beekmantown 

 and Chazy is well exposed, the lowest Chazy being characterized by a large 

 Lingiila while the upper Beekmantown contains an Isockiliiia known to 

 occur in that horizon in other localities. 



1904. Seei.y, H. M. The Stromatoceria of Isle La JVIotte, Vermont. Report of 



the Vermont State Geologist, New Series, Vol. 4, p. 144. 



In this paper Professor Seely describes Stroiiiatoceriwn lamot tense n. s. 

 and its variety Chazyamiiu, Stroniatoceriuin ? moniliferwn n. s. and Cryp- 

 tozoon ? perkinsi n. s. from the Chazy formation at Isle La Motte, Vt., and 

 Chazy, N. V. 



1905. CusHi.NG, H. P. Geology of the Vicinity of Little Falls, Herkimer County. 



Bulletin of the New York State Museum, No. 77, January, 1905. 



The absence of the Chazy formation in the Mohawk Valley is said to be 

 due to a progressively diminishing rate of subsidence from north to south. 



1905. Raymond, P. E. The Trilobites of the Chazy Limestone. Annals of the 

 Carnegie Museum, \'ol. 3, pp. 328-386, March, 1905. 



In this paper are described and figured all the previously known species 

 of trilobites from the Chazy formation, together with a number of new 

 species. Since its publication, Psendosph<e)-exochus mars (Hudson) and 

 Helioniera sol (Billings) have been added to the Chazy trilobite fauna. 



1905. Hudson, George H. Contributions to the Fauna of Chazy Limestone on 

 Valcour Island, Lake Champlain. Report of the New York State Paleon- 

 tologist for 1903, p. 270, April, 1905. 



