622 ALFRED W. G. WILSON 



Adams also the author is indebted for the photographs from 

 which Figs. 6, 7 and 8 were prepared. He has also to acknowl- 

 edge the kindness of Mr. James A. Smart, deputy minister of the 

 interior, from whom the photographs to prepare Figs. 9, 10, ii, 

 and 12 were obtained. 



The original photographs from which the figures were made 

 are deposited in the Collection of Geological Photographs of 

 McGill University, Montreal. 



PHYSIOGRAPHIC CONTROLS. 



One of the most interesting problems for study presented by 

 the Laurentian Peneplain is the control which the type of topog- 

 raphy here developed has had upon the occupation and 

 exploration of the region. Stretching, as it does, -from the 

 frozen Arctic to the temperate regions of central Ontario, and 

 from the ocean border on the east to the mid-continental region 

 of the great plains on the west, in its different parts it presents 

 many phases of the operation of climatic controls, which affect 

 its flora, its fauna, and its human occupation. 



The uplands of Labrador and the far northwest of the region 

 (north Keewatin, and northeast Mackenzie) are devoid of trees, 

 the vegetation being confined to the lower orders of plants. 

 Next southward we find the belt of conifers stretching all across 

 the region from Hamilton Inlet to northwest of Great Slave 

 Lake, the trees increasing in size and variety with decrease of 

 latitude. In the central parts deciduous trees abound. Although, 

 in general, throughout the region we find uniformity of features, in 

 structure and development there is a great diversity of detail. 

 The enormous number of the lakes and streams, the widespread 

 distribution of the forests, the general uniformity of the topog- 

 raphy, and the climatic characteristics of the region, have all 

 contributed to make it the home of those animals whose flesh is 

 valuable for food, and whose pelts are valuable for clothing or 

 (secondarily) as an article of commerce. The remarkably even 

 character of the region, the character of the flora, and the pro- 

 tection offered by climatic conditions even now make possible 

 the existence of those vast herds of caribou (comparable to the 



