422 THE GEOGRAPHICAL DISTRIBUTION OF THE SCYPHOMEDUSiE, 



We will first of all consider the moi*e considerable of the warm 

 and cold Equatorial, and Polar currents, which tend to equalize the 

 warmth of the Equatorial and the cold of the Polar water. 



THE COLD CURRENTS. 



Two mighty currents of cold water flow from the Antarctic 

 regions in a north-easterly direction towards the zone of the 

 Tropics. The one approaches Tasmania and the other Cape 

 Nuyts, the south-west point of Australia. Each current divides at 

 the spot where it nears the coast. As well from Tasmania as from 

 Cape Nuyts extend sub-marine elevations of the ground of the 

 ocean towards the south-west, which, like a ploughshare, divide 

 the currents in two equal parts before they reach the coast. 



The eastern branch of the western current, and the western 

 branch of the eastern, bend round in a half circle and are lost in 

 the Great Australian Bight. The eastern branch of the western 

 Polar current bends round to the east and south-east, but remains 

 at a distance from the coast ; the branch coming from the eastern 

 Polar current on the contrary bends towards the north-west and 

 west, and flows along the coast of this part of Australia, namely, 

 Victoria. 



The western branch of the western Polar current alters its 

 course from a northern to a western direction. During its 

 course northwards it washes the west coast of Australia. 



The eastern branch of the eastern current flows due north-east 

 from Tasmania to Cape Van Diemen, the north-west point of 

 New Zealand. 



In its middle course, as we shall see further on, it passes 

 beneath a warm current coming from the equator, and on the 

 north-eastern side of this current it appears again. These cold 

 currents are surface currents, but still appear to extend to a great 

 depth. Only here and there in deep water we find other currents 

 than on the surface. 



