THE LAURENTIAN PENEPLAIN 62 1 



ments and southward and westward from the English posts on 

 Hudson Bay. Records of some of these exploratory journeys 

 and records of the travels of the Jesuit missionaries are still 

 extant. Later explorations, incident to the continued search for 

 a northwest passage from Hudson Bay, led several parties across 

 the far northwest portion of the area. Until quite recently the 

 imperfect records of these travelers constituted the only available 

 accounts of large areas of the interior. 



The period of active geographic and geologic investigation of 

 this region really began about fifty years ago with Logan's 

 historic work on the geology of the Archaean districts north of 

 the Ottawa River. Since that time more or less systematic 

 geographic and geologic explorations have been carried on, 

 chiefly by the Geological Survey of Canada, but in part by the 

 Topographic Survey's branch of the Department of the Interior 

 at Ottawa. At present we have at least a general knowledge of 

 the main geographic features of the Laurentian Peneplain, 

 although much still remains to be done. , 



The information used in the present paper, outside that from 

 the writer's personal observations, has been derived chiefly from 

 the reports of the explorations of A. P. Low in Labrador, of Dr. 

 Robert Bell and Dr. A. E. Barlow in the districts to the south 

 and southwest of James Bay, and of J. B. Tyrrell, and J. VV. 

 Tyrrell in the country to the east of Hudson Bay. In the papers 

 by A. P. Low, J. B. Tyrrell, J. W. Tyrrell, and Dr. George M. 

 Dawson, to which reference is made below, nearly complete 

 bibliographies will be found dealing with the literature of the 

 subject. It does not seem necessary to reproduce the bibliog- 

 raphy here. 



The writer is indebted to Mr. A. P. Low, of the Geological 

 Survey Department, Ottawa, for some suggestions to which due 

 reference is made in the text, and also for a number of photo- 

 graphs from central Labrador, from which Figs. 2, 3, 4, 5 and 

 13 were prepared. He wishes also to acknowledge his indebted- 

 ness to Dr. F. D. Adams, of McGill University, Montreal, and 

 to Bailey Willis, of the U. S. Geological Survey, for critical 

 readings of portions of the manuscript of this paper. To Dr. 



