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NATURALIST'S GUIDE TO THE AMERICAS 



the rim of the plateau, from a central 

 crest lying approximately along the 

 53rd parallel between the 65th and 

 70th meridians, west longitude. The 

 plateau is bordered in the northeastern 

 portion, along the Atlantic seaboard by 

 ranges of sharp, unglaciated mountains, 

 beginning about latitude 55° N. and 

 extending northward to Cape Ohidley, 

 with maximum altitudes of 6000 ft. 

 inland from Saglek Bay; but elsewhere 

 the rim of the plateau does not rise 

 above the general level of the plateau. 

 The entire inland area of the plateau is 

 comparatively level, traversed only by 

 low, rounded, roughly parallel ridges of 

 crystalline rocks, so that except for a 

 very few places, there is not in the entire 

 plateau area 200,000 sq. mi., a difference 

 of level of more than 400 ft. The general 

 surface is further modified by low 

 moraines extending in a general way the 

 same direction as the slope of the 

 country, yet appreciably modifying the 

 preglacial drainage sj'stem of the terrain. 



Soil 



Most of the soil of the peninsula is a 

 boulder-studded, infertile, glacial till, 

 derived from the Archean rocks. Over 

 wide areas it is very sandy. The soil 

 along the river valleys has been modified 

 and enriched by redeposition and with a 

 consequent heavier growth of vegeta- 

 tion. The richest soils bearing the 

 best development of vegetation are the 

 alluvial-topped soils along the coast 

 and the inlets, and the areas of limestone 

 and shale outcrops of the supposed early 

 Cambrian rocks. 



Drainage 



As a consequence of the damming of 

 the valleys and basins of the streams 

 of the Labrador plateau by the masses 

 of glacial till and moraines, the whole 

 area is dotted with myriads of lakes and 

 pools, that occupy at least a fourth of 

 the entire area. They vary in size from 

 small narrow ponds to large extensive 

 lakes hundreds of square miles in area, 

 most of them relatively shallow, some 

 deep. In addition to the great lake 



areas, large portions of the plateau 

 are occupied by damp, boggy, tundra 

 with defective drainage, almost lake- 

 like in character. 



A perfect network of streams connects 

 these lakes and ponds, all interlocking so 

 closely that no great distances separate 

 the headwaters; and since above the 

 rapids near the coast, the streams and 

 lakes are generally navigable by canoes, 

 water travel is relatively easy through- 

 out the plateau, with few portages more 

 than 2 or 3 mi. long. 



Three principal watersheds comprise 

 the peninsular north of the Height of 

 Land. The eastern is drained prin- 

 cipally by the tributaries of Hamilton 

 Inlet- — the northern is drained by the 

 Koksoak, the largest and longest river 

 of Labrador, the George, the Whale, 

 and the Leaf; the western, the most 

 extensive of the peninsula, is drained 

 by the Nastapoka to the north, the 

 Little Whale and the Great Whale about 

 the middle, and the Big and Last Main 

 to the south. 



The water in the pools, lakes, and 

 streams is remarkably clear, quite 

 different from the dark-brown waters 

 of the Laurentian basin. Because the 

 summer season is short, the swamps and 

 tundra from which most of the streams 

 and lakes drain their water are thawed 

 only to a depth of 12 to 18 in., and 

 vegetable decomposition, particularly of 

 the sphagnum mosses, is negligible. 



CLIMATE 



The climate of the plateau of Labrador 

 is generally and distinctly Arctic. Ex- 

 cept at the heads of the deeper fjords 

 and inlets of the southern portion of the 

 east coast, where the diurnal range of 

 temperature is from 45° to 90°, and the 

 average temperature in summer is 

 above 50°, the temperatures for the 

 year are characteristically sub-Arctic. 



Though situated in the same latitude 

 as some of the most pleasant and most 

 productive lands of Europe, Labrador 

 is chilled by the cold waters of the 

 Greenland current along its eastern 

 shore, and_^by the prevaiUng westerly 



