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THE FOSSIL MOLLUSC AN FAUNAS OF THE MARL 
DEPOSITS OF THE OTTAWA DISTRICT 
By E. J. Whittaker 
INTRODUCTION 
Many deposits ■ of marl throughout the Ottawa district 
contain freshwater molluscan remains and, more rarely, terres- 
trial shells. One of the most accessible and best known occurs 
at McKay (formerly Hemlock) lake, Rockcliffe, 3 miles east of 
Ottawa. Deposits of the same character occur at Colton lake, 
near Renfrew, and Mink lake, near Eganville, Another locality 
is represented by a collection of fossils in the Victoria Memorial 
Museum labelled marl, lot 7, Junction gore, Gloucester tp., 
Carleton co., now included in the town of Eastview. 
Marl from all these localities was formerly used in making 
lime and also, when mixed with clay, in the manufacture of 
cement. In the early days, and even yet in places, marl is 
used for whitewashing buildings. 
The McKay Lake marl beds which are of Recent age were 
deposited just after the retreat of the last marine invasion and 
antedate the historic period by many centuries. The other 
deposits are somewhat younger. 
1 The writer is indebted to E. M. Kindle, of the Geological Survey, 
Canada, at whose suggestion this study was initiated, for valuable assistance 
and advice; to Dr. F. C. Baker, of the University of Illinois; and to Miss 
A. E. Wilson and M. E. Wilson, of the Geological Survey, for procuring 
material for him from Mink and Colton lakes respectively. 
