Collingwood black shales. — East of Little Current, 

 at an elevation of 50 feet (15 m.) above the lake, black fissile 

 shales, to which Raymond has applied the term "Colling- 

 wood", rest upon Trenton strata containing Tetradium. 

 At the base, these Collingwood shales are interbedded 

 with limestones similar lithologically to the Trenton 

 limestones beneath. Formerly, these shales were identified 

 with the Utica of New York, but they contain a different 

 fauna such as the trilobite long known as Asaphus, now 

 (Ogygites) canadensis, also Triarthrus fischeri, and others. 

 A thickness of only 11 feet (3.4 m.) of Collingwood shale 

 is exposed on the hill east of Little Current, but the total 

 thickness equals at least twice that amount. Three miles 

 (4.8 km.) southeast of Little Current, on the "shore road" 

 to Sheguindah, the Collingwood shales are overlaid by 

 softer clay shales which form the base of the undoubted 

 Cincinnatian section. 



The common Collingwood fossils are: — 



Diplograptus quadrimucronatus Hall. 

 Ogygites canadensis (Chapman). 

 Triarthrus fischeri Billings. 



THE SILURIAN OF THE EASTERN PART OF 

 MANITOULIN ISLAND. 



BY 



Merton Y. Williams. 



INTRODUCTION. 



History. — Manitowaning to-day shows few traces of 

 its early history. Storehouses and a grist mill occupy 

 the land jutting out from the front of the escarpment; the 

 main town is on a higher level a short distance inland. A 

 few buildings occupy the intermediate terraces, and on the 

 rising slope above the wharves, the low rambling Indian 

 Agency stands with its official flagstaff, though stripped 

 of the stockade which once surrounded it. Where the 

 agency now is, 1,500 Indians representing the Chippewa, 



