424 THE GEOGRAPniCAL DISTRIBUTION OF THE SCVPHOMEDUSvE, 



and flows through these Straits in a westerly direction. This 

 current, in the shallow parts of the Straits, is so strong that even 

 in the calmest weather the sea is very much disturbed. On the 

 surface of the water, between New Zealand, Australia, and New 

 Caledonia, slight whirlpools are found. 



A current in the Torres Straits, similar to the one in Bass' 

 Straits, flows in a westerly direction in the pass between Australia 

 and New Guinea. Again, a stream coming from the south-west 

 is found on the north-west coast which.flows along the coast of De 

 Wittsland : another more important current coming from south- 

 east passes Cape Leuwin. 



A current, not discoverable on the surface, to the south of the 

 great Australian Bight, flows in an easterly direction along the 

 bottom of the sea. 



The sources from which I have collected these assumptions 

 contradict each other in so many and such important points that 

 it has been very difficult to make a clear representation of the 

 facts ; and although from these grounds there must be numerous 

 deficiencies in my description still in the more important point it 

 will be found near the truth. 



The depths of the sea, in that part under our survey, varies 

 from 4000 to 5000 meters. The ground of the sea rises every- 

 where pretty gradually to the level of 200 meters from the surface 

 at an average distance from the coast of 20 kilometers. 



The level of 3,650 meters (2,000 fathoms), does not surround 

 Australia on all sides ; there are shallows, which on one side unite 

 Australia with Asia across the Islands towards Cochin China, and 

 on the other across New Zealand with South America. (1) In 

 these shallows the sea does not reach the depths of 3,650 meters. 

 The south-east of Australia is the steepest in descent. The 

 Geographic Distribution of the Rhizostompe within this district 

 depends, as I will attempt to show in the following pages, on 

 these currents on the one hand, and the configuration of the coast 

 on the other. 



(1.) F. llutton. On the origin of the Fauna and Flora of New Zealand. 

 New Zealand Journal of Science, Jan. 1884. 



