Raymond: Pelecypoda of Chazy Formation. 327 



Raymond; Beyrichial clavigera, Jones; Beyrichia? clavigera clavijracta, 

 Jones; IsocMlina Ottawa mtermedia, Jones; Isochilina lahellosa, Jones; 

 Leper ditia amygdalina, Jones. 



An examination of the strata exposed at Grenville, Quebec, and at 

 the mouth of the Little Rideau River a few miles below Grenville, 

 shows that the ostracod- and trilobite-bearing limestone there is not 

 the same as the "Chazy limestone" (Pamelia) at L'Original and 

 Ottawa, but lies beneath the Chazy, and belongs to the Beekmantown. 

 This necessitates the removal of the following species from the Chazy 

 to the Beekmantown: Bathyurus angelina, Billings; Leperditia cana- 

 densis, Jones; Priniitia logani, Jones; Isochilina Ottawa, Jones. 



This removes what had been one of the anomalies of the Chazy 

 fauna, namely, the Bathyurus. Bathytirus is one of the strictly 

 American genera, and its presence is usually an indication that the 

 fauna is that of the interior sea. The other trilobites of the Chazy, 

 on the other hand, are European or cosmopolitan genera, and the 

 fauna as a whole is of the Atlantic facies. 



At a later date, the Atlantic, or Arctic and interior faunas mingled, 

 and we have in the Black River Bathyurus associated with such 

 European genera as Basilicus. 



Chazy of Quebec and the Mingan Islands. 



The writer had occasion, in the summers of 1910 to 1912, to go 

 over most of the exposures of the Chazy in the province of Quebec, 

 except the Mingan Islands, and was surprised to find that nowhere 

 were there exposures of strata older than the Upper Chazy of the 

 section in the Champlain Valley. 



The so-called Chazy in the section between Philipsburg and St. 

 Armand contains no Chazy fossils, and belongs to the Beekmantown. 

 The "Chazy slates" of Ells^^ at Mystic and vicinity are the shales 

 and conglomerates of the Levis formation. The strata referred to 

 the Chazy at St. Dominique belong to the upper division of the 

 Chazy. The limestones at Caughnawaga, St. Martins Junction, 

 Mile End, and elsewhere in the vicinity of Montreal all belong to 

 the Upper Chazy, and have a sandstone at the base, this sandstone 

 resting on the Beekmantown without the intervention of any strata 

 which can be correlated with the Middle or Lower Chazy. At 

 Joliette, fifty miles northeast of Montreal, the Chazy is a thin sandy 

 limestone with a small fauna. 



13 Ann. Rept. Geol. Survey Canada, Vol. VII, 1896, pt. J, p. 34. 



