ON NORTH AMEniCAN ZOOLOGY. 127 



which may he traced on the map as the River and Lake Wini- 

 peg, lower part of the Saskatchewan, Beaver Lake, Mississippi, 

 , Athabascow River and Lake, Slave River and Great Slave Lake, 

 from whence Mackenzie's River issuing sweeps round the 

 north end of the zone, and approaches the base of the Rocky 

 Mountains within^^the Arctic circle. This longitudinal water- 

 course lying nearly at a right angle with the transverse valley 

 of the St. Lawrence cuts off a large north-east corner of the 

 continent, including the Canadas, Labrador, Rupert's Land, 

 and the more northern districts. Though this tract, which 

 equals Europe in extent, has a greatly varied surface and in- 

 cludes some high groups of hills, it possesses no continuous 

 mountain ranges of great elevation, nor indeed any peaks which 

 reach the limits of perpetual snow. Its lakes are numerous 

 and often large, the proportion of water to land being great. 

 In a zoological point of view the district admits of being divided 

 into two portions : the northern one, destitute of trees and there- 

 fore named the '' barren grounds," lies beyond a line running 

 W.N.W. from Hudson's Bay in the 60th parallel to Great 

 Bear Lake in the 65th. The southerly portion is wooded, antl 

 although it embraces many degrees of latitude it presents a 

 surprising uniformity everywhere in its ferine inhabitants. 

 The great inland sea of Hudson's Bay, occupying the centre of 

 the whole north-east district, (the lands north of Hudson's 

 Strait being considered as part of it,) materially influences its 

 temperature, and consequently its capability of supporting animal 

 life. The south and south-west shores of this bay are flat and 

 swampy with muddy beaches, whereon vast flocks of water- 

 fowl halt for a time in the course of their autumn migrations 

 from the northern breeding-places to their southerly winter 

 haunts. 



On the Pacific side of the Rocky Mountains we have to the 

 northward an expanded wing, as it were, of the continent pro- 

 longed by the peninsula of Alaska and the Aleutian Islands, 

 and similar in geological and zoological characters, as far as has 

 been ascertained, to the eastern barren grounds. Further to 

 the south the coast line approaches the Rocky Mountains, but 

 it recedes again in Upper California; while Lower or old Cali- 

 fornia runs out in a peninsular form like Florida, intercepting 

 the Gulf of Cortes or the Vermilion Sea, which though much 

 narrower than the Gulf of Mexico extends nearly as far north- 

 wards. The Pacific coast is flanked at some distance by a 

 range termed by Humboldt the " Californian Maritime Alps ". 

 These are in general nearly parallel to the Rocky Mountains, 

 and become more and more elevated as they proceed northwards 



